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 A352625 #8 Mar 27 2022 13:41:23
%S A352625 1,2,7,59,1529,83313,7869898,1687054711,1123424582771,
%T A352625 1662315215971057,4257998884448335457,23385756731869683322514,
%U A352625 397068399296019032727466599,15886280085653574502219650145963,1107464108502549897934954766675333353,157131202095317153373302215985417166354641
%N A352625 A (25,-29) Somos-4 sequence.
%C A352625 Hankel transform of A188314 with first term omitted.
%F A352625 a(n) = (25*a(n-1)*a(n-3) - 29*a(n-2)^2)/a(n-4) for all n in Z.
%F A352625 a(n) = (29*a(n-1)*a(n-4) - 13*a(n-2)*a(n-3))/a(n-5) for all n in Z.
%F A352625 a(n) = b(1-2*n) = b(2*n+2) = A188313(-1-n) for all n in Z where b(n) = A006720(n).
%e A352625 G.f.: 1 + 2*x + 7*x^2 + 59*x^3 + 1529*x^4 + 83313*x^5 + ...
%e A352625 a(2) = 7 = 2*16 - 5*5 = det([2, 5; 5, 16]).
%t A352625 b[ n_] := If[OddQ[n], a[-(n-1)/2], a[n/2-1]]; a[ n_] := If[-3<=n<=1, {23, 3, 1, 1, 2}[[n+4]], 2*b[1-n]^3*b[2-n] + b[-n]^2*(b[2-n]*b[3-n] - b[1-n]*b[4-n])];
%Y A352625 Cf. A006720, A188313, A188314.
%K A352625 nonn
%O A352625 0,2
%A A352625 _Michael Somos_, Mar 24 2022