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 A146126 #12 Mar 23 2018 12:28:50 %S A146126 0,235,9716,43201,125064,290427,583948,1060251,1783944,2829619, %T A146126 4281852,6235203,8794216,12073419,16197324,21300427,27527208,35032131, %U A146126 43979644,54544179,66910152 %N A146126 Number of n X n arrays of squares of integers with every (n-2) X (n-2) subblock summing to 5 and every element equal to at least one neighbor. %F A146126 Empirical (for n>=8): a(n) = 416*n^4 - 6704*n^3 + 42495*n^2 - 127724*n + 155688. - _Vaclav Kotesovec_, Nov 30 2012 %F A146126 Conjectures from _Colin Barker_, Mar 23 2018: (Start) %F A146126 G.f.: x^5*(235 + 8541*x - 3029*x^2 + 3869*x^3 + 1132*x^4 - 1212*x^5 + 430*x^6 + 18*x^7) / (1 - x)^5. %F A146126 a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>12. %F A146126 (End) %K A146126 nonn %O A146126 4,2 %A A146126 _R. H. Hardin_, Apr 14 2009