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 A245872 #11 Nov 05 2018 03:05:12 %S A245872 16,103,256,549,960,1579,2368,3433,4720,6351,8256,10573,13216,16339, %T A245872 19840,23889,28368,33463,39040,45301,52096,59643,67776,76729,86320, %U A245872 96799,107968,120093,132960,146851,161536,177313,193936,211719,230400,250309 %N A245872 Number of length 3+2 0..n arrays with some pair in every consecutive three terms totalling exactly n. %H A245872 R. H. Hardin, <a href="/A245872/b245872.txt">Table of n, a(n) for n = 1..210</a> %F A245872 Empirical: a(n) = 2*a(n-1) + a(n-2) - 4*a(n-3) + a(n-4) + 2*a(n-5) - a(n-6). %F A245872 Conjectures from _Colin Barker_, Nov 04 2018: (Start) %F A245872 G.f.: x*(16 + 71*x + 34*x^2 - 2*x^3 + 2*x^4 - x^5) / ((1 - x)^4*(1 + x)^2). %F A245872 a(n) = 1 + 5*n + 13*n^2 + 5*n^3 for n even. %F A245872 a(n) = -5 + 3*n + 13*n^2 + 5*n^3 for n odd. %F A245872 (End) %e A245872 Some solutions for n=10: %e A245872 7 7 7 5 1 9 3 6 4 9 10 10 5 2 9 0 %e A245872 3 4 3 5 1 9 10 4 2 1 8 0 7 4 5 6 %e A245872 5 6 5 4 9 1 7 10 8 4 2 10 5 6 5 4 %e A245872 5 2 7 5 5 4 3 0 8 6 4 0 5 4 5 5 %e A245872 4 4 3 6 5 9 10 6 2 4 6 6 8 1 3 6 %Y A245872 Row 3 of A245869. %K A245872 nonn %O A245872 1,1 %A A245872 _R. H. Hardin_, Aug 04 2014