This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A080875 #17 Jul 14 2024 12:22:08
%S A080875 1,1,6,11,71,131,846,1561,10081,18601,120126,221651,1431431,2641211,
%T A080875 17057046,31472881,203253121,375033361,2421980406,4468927451,
%U A080875 28860511751,53252096051,343904160606,634556225161,4097989415521
%N A080875 a(n)*a(n+3) - a(n+1)*a(n+2) = 5, given a(0)=a(1)=1, a(2)=6.
%H A080875 Seiichi Manyama, <a href="/A080875/b080875.txt">Table of n, a(n) for n = 0..1500</a>
%H A080875 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0, 12, 0, -1).
%F A080875 G.f.: (-x^3 - 6*x^2 + x + 1)/(x^4 - 12*x^2 + 1).
%F A080875 a(n+4) = 12*a(n+2)-a(n). [_Richard Choulet_, Dec 04 2008]
%F A080875 a(n) = (1/4 + ((sqrt(6 + sqrt(35)) - sqrt(6 - sqrt(35)))/(4*sqrt(35))))*(sqrt(6 + sqrt(35)))^n + (1/4 + ((sqrt(6 + sqrt(35)) - sqrt(6 - sqrt(35)))/(4*sqrt(35))))*(sqrt(6 - sqrt(35)))^n + (1/4 - ((sqrt(6 + sqrt(35)) - sqrt(6 - sqrt(35)))/(4*sqrt(35))))*( - sqrt(6 + sqrt(35)))^n + (1/4 - ((sqrt(6 + sqrt(35)) - sqrt(6 - sqrt(35)))/(4*sqrt(35))))*( - (sqrt(6 - sqrt(35))))^n. [_Richard Choulet_, Dec 06 2008]
%t A080875 LinearRecurrence[{0,12,0,-1},{1,1,6,11},30] (* _Harvey P. Dale_, Jul 14 2024 *)
%Y A080875 Cf. A080871, A080872, A080873, A080874.
%Y A080875 Bisections are A023038 and A077417.
%K A080875 nonn
%O A080875 0,3
%A A080875 _Paul D. Hanna_, Feb 22 2003