LinearRecurrence[{3, -4, 4, -4, 4, -4, 4, -4, 4, -3, 1}, {2, 2, 4, 10, 16, 28, 48, 76, 110, 144, 182}, 30]
a(n) = (1)·a(n-11) + (-3)·a(n-10) + (4)·a(n-9) + (-4)·a(n-8) + (4)·a(n-7) + (-4)·a(n-6)
+ (4)·a(n-5) + (-4)·a(n-4) + (4)·a(n-3) + (-3)·a(n-2) + (3)·a(n-1) [NB: voir PDF]
Conditions initialesInitial terms : a(0)=2, a(1)=2, a(2)=4, a(3)=10, a(4)=16, a(5)=28, a(6)=48, a(7)=76, a(8)=110, a(9)=144, a(10)=182
Formule complète — défile horizontalement :
Full formula — scroll horizontally:
$$a(n) = - \frac{125 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 40 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 120 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 64 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 160 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{1055 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 80 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 240 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 128 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 320 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{1055 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 80 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 240 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 128 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 320 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{1205 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 160 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 480 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 256 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 640 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{3235 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 320 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 960 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 512 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1280 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{6555 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 320 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 960 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 512 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1280 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{2180 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{384 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{1714 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{3390 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{125 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 40 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 120 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 160 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 64 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{1055 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 80 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 240 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 320 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 128 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{1055 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 80 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 240 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 320 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 128 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{1205 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 160 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 480 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 640 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 256 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{6555 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 320 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 960 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1280 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 512 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{3235 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 320 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 960 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 1280 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 512 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} - \frac{2180 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{384 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{3390 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{1714 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}{- 640 \sqrt{5} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1920 \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} - 2560 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n} + 1024 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{5 - \sqrt{5}}\right)^{n}} + \frac{375 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 40 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 320 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{375 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 40 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 320 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{235 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 80 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 400 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 640 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1600 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{275 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 160 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 800 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 1280 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{3385 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 320 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1600 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 2560 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 6400 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{3625 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 320 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1600 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 2560 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 6400 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{2700 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{640 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{510 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{2530 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} + 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{375 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 40 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 320 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{375 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 40 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 320 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{235 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 80 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 400 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 1600 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 640 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{275 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 160 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 800 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 3200 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1280 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{3625 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 320 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1600 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 6400 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 2560 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{3385 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 320 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 1600 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 6400 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 2560 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{2700 \cdot 2^{\frac{n}{2}} \cdot 8^{n}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{640 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} - \frac{2530 \cdot 2^{\frac{n}{2}} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + \frac{510 \cdot 2^{\frac{n}{2}} \sqrt{5} \cdot 8^{n} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}{- 640 \sqrt{5} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 3200 \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} - 12800 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n} + 5120 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(- 2 \sqrt{2} + 2 \sqrt{10} - 4 i \sqrt{\sqrt{5} + 5}\right)^{n}} + 2 n^{2} - 2 n - \frac{3385 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{320 \sqrt{5} + 1600 - 6400 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 2560 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{2700 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 - 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{640 \sqrt{5} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 - 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{375 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{40 \sqrt{5} + 200 - 800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 320 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{275 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{160 \sqrt{5} + 800 - 3200 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 1280 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{2530 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 - 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{510 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 - 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{3625 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{320 \sqrt{5} + 1600 - 6400 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 2560 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{235 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{80 \sqrt{5} + 400 - 1600 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 640 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{375 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} - i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{40 \sqrt{5} + 200 - 800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} - 320 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{375 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{40 \sqrt{5} + 200 + 320 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{235 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{80 \sqrt{5} + 400 + 640 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 1600 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{3625 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{320 \sqrt{5} + 1600 + 2560 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 6400 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{510 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 + 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{2530 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 + 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{275 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{160 \sqrt{5} + 800 + 1280 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 3200 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{375 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{40 \sqrt{5} + 200 + 320 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{640 \sqrt{5} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 + 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{2700 \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{640 \sqrt{5} + 3200 + 5120 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 12800 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} + \frac{3385 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} - \frac{1}{4} + i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}}\right)^{n}}{320 \sqrt{5} + 1600 + 2560 \sqrt{5} i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}} + 6400 i \sqrt{\frac{5}{8} - \frac{\sqrt{5}}{8}}} - \frac{3235 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{320 \sqrt{5} + 960 - 1280 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 512 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{6555 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{320 \sqrt{5} + 960 - 1280 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 512 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{1714 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 - 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{2180 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 - 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{125 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{40 \sqrt{5} + 120 - 160 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 64 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{384 \sqrt{5} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 - 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{3390 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 - 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{1205 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{160 \sqrt{5} + 480 - 640 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 256 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{1055 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{80 \sqrt{5} + 240 - 320 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 128 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{1055 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} - i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{80 \sqrt{5} + 240 - 320 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} - 128 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{1055 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{80 \sqrt{5} + 240 + 128 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 320 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{1055 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{80 \sqrt{5} + 240 + 128 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 320 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{1205 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{160 \sqrt{5} + 480 + 256 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 640 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{3390 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 + 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{384 \sqrt{5} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 + 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{125 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{40 \sqrt{5} + 120 + 64 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 160 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - \frac{2180 \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 + 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{1714 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{640 \sqrt{5} + 1920 + 1024 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 2560 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{6555 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{320 \sqrt{5} + 960 + 512 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 1280 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} + \frac{3235 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} \left(\frac{1}{- \frac{\sqrt{5}}{4} + \frac{1}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}}\right)^{n}}{320 \sqrt{5} + 960 + 512 \sqrt{5} i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}} + 1280 i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}} - 4$$
Séquence (30 premiers termes)Sequence (first 30 terms)
2, 2, 4, 10, 16, 28, 48, 76, 110, 144, 182, 222, 264, 310, 356, 408, 468, 536, 610, 684, 762, 842, 924, 1010, 1096, 1188, 1288, 1396, 1510, 1624
La fonction génératrice est :
The generating function is:
$$G(z) = \begin{align*} \normalsize EJS\_P2P2P4P10P16P28P48P76P110P144P182\_P1N3P4N4P4N4P4N4P4N4P3_{GF}(x) = \frac{- 4 x^{10} + 2 x^{9} - 2 x^{8} - 4 x^{7} - 4 x^{6} - 4 x^{5} - 2 x^{4} + 2 x^{3} - 6 x^{2} + 4 x - 2}{x^{11} - 3 x^{10} + 4 x^{9} - 4 x^{8} + 4 x^{7} - 4 x^{6} + 4 x^{5} - 4 x^{4} + 4 x^{3} - 4 x^{2} + 3 x - 1} \end{align*} $$
Propriété remarquable :Remarkable property:
le polynôme caractéristique de degré 11 admet les 10 racines de l'unité
$e^{2i\pi k/10}$ pour $k=1,...,9$ plus la racine 1 avec multiplicité 2.
C'est pourquoi la formule fait apparaître $\sqrt{5}$, $\sqrt{2}$, $\sqrt{10}$,
$\sqrt{5-\sqrt{5}}$ et $\sqrt{5+\sqrt{5}}$ — exactement les valeurs exactes de
$\sin(\pi/5)$, $\cos(\pi/5)$, $\sin(2\pi/5)$, $\cos(2\pi/5)$.
La formule complète contient plusieurs milliers de symboles LaTeX
(voir PDF) — pourtant la séquence résultante croît modestement de façon
quasi-quadratique. C'est le cas le plus spectaculaire de contraste entre
la complexité de la formule et la sobriété de la dynamique.
the degree-11 characteristic polynomial has all 10 roots of unity
$e^{2i\pi k/10}$ for $k=1,...,9$ plus root 1 with multiplicity 2.
Hence the formula features $\sqrt{5}$, $\sqrt{2}$, $\sqrt{10}$,
$\sqrt{5-\sqrt{5}}$ and $\sqrt{5+\sqrt{5}}$ — exactly the closed forms of
$\sin(\pi/5)$, $\cos(\pi/5)$, $\sin(2\pi/5)$, $\cos(2\pi/5)$.
The double root at 1 produces the polynomial term $2n^2 - 2n - 4$.
The complete formula contains several thousand LaTeX symbols
(see PDF) — yet the resulting sequence grows modestly, almost quadratically.
This is the most spectacular case of contrast between formula complexity
and dynamical simplicity.