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 A276256 #14 Aug 26 2016 09:25:29 %S A276256 1,1,1,9,121,17161,33189121,9112869675009,4839170130591864288001, %T A276256 705579627764469400107962287271157001, %U A276256 54630717750911142085059359537536676834981970103054482555001 %N A276256 A nonlinear recurrence of order 3: a(1)=a(2)=a(3)=1; a(n)=(a(n-1)+a(n-2)+1)^2/a(n-3). %C A276256 All terms are perfect squares. %H A276256 Seiichi Manyama, <a href="/A276256/b276256.txt">Table of n, a(n) for n = 1..16</a> %F A276256 a(n) = A276258(n)^2. %F A276256 a(n) = 16*a(n-1)*a(n-2) - 2a(n-1) - 2a(n-2) - 2 - a(n-3). %F A276256 a(n)*a(n-1)*a(n-2) = ((a(n) + a(n-1) + a(n-2) + 1)/4)^2. %Y A276256 Cf. A276095. %K A276256 nonn %O A276256 1,4 %A A276256 _Seiichi Manyama_, Aug 25 2016