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 A375309 #14 Aug 14 2024 08:37:24
%S A375309 0,0,1,1,7,11,51,105,399,967,3299,8789,28271,79443,247507,716353,
%T A375309 2193583,6452639,19575075,58095597,175350735,522947755,1574075603,
%U A375309 4706879321,14146450127,42363311991,127217598691,381275400325,1144458922159
%N A375309 Number of walks of length n along the edges of a dodecahedron graph between two vertices at distance two.
%H A375309 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (2,10,-16,-25,30).
%F A375309 For n>=6, a(n) = 2*a(n-1) + 10*a(n-2) - 16*a(n-3) - 25*a(n-4) + 30*a(n-5).
%F A375309 From _Stefano Spezia_, Aug 13 2024: (Start)
%F A375309 G.f.: x^2*(1 - x - 5*x^2 + 3*x^3)/((1 - x)*(1 + 2*x)*(1 - 3*x)*(1 - 5*x^2)).
%F A375309 a(n) = (3*5^(n/2)*(1 + (-1)^n) + 3^(1+n) + (-1)^n*2^(1+n) - 5)/60 for n > 0. (End)
%t A375309 LinearRecurrence[{2, 10, -16, -25, 30}, {0, 0, 1, 1, 7, 11}, 30] (* _Amiram Eldar_, Aug 13 2024 *)
%Y A375309 Cf. A054883.
%K A375309 nonn,easy
%O A375309 0,5
%A A375309 _Miquel A. Fiol_, Aug 11 2024