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 A223600 #9 Aug 21 2018 10:04:35 %S A223600 256,256,1504,6736,32768,156592,755200,3643024,17608064,85179184, %T A223600 412367104,1997306896,9677417600,46900761520,227339596288, %U A223600 1102103488912,5343259128704,25906912147504,125615423519488,609091866864400 %N A223600 Petersen graph (8,2) coloring a rectangular array: number of 2 X n 0..15 arrays where 0..15 label nodes of a graph with edges 0,1 0,8 8,14 8,10 1,2 1,9 9,15 9,11 2,3 2,10 10,12 3,4 3,11 11,13 4,5 4,12 12,14 5,6 5,13 13,15 6,7 6,14 7,0 7,15 and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an edge of this graph. %C A223600 Row 2 of A223599. %H A223600 R. H. Hardin, <a href="/A223600/b223600.txt">Table of n, a(n) for n = 1..210</a> %F A223600 Empirical: a(n) = 6*a(n-1) + 3*a(n-2) - 42*a(n-3) - 8*a(n-4) + 48*a(n-5) for n>6. %F A223600 Empirical g.f.: 16*x*(16 - 80*x - 50*x^2 + 481*x^3 + 40*x^4 - 456*x^5) / ((1 + 2*x)*(1 - 8*x + 13*x^2 + 16*x^3 - 24*x^4)). - _Colin Barker_, Aug 21 2018 %e A223600 Some solutions for n=3: %e A223600 ..2..3..4...11..3..4....0..8.14...15..7..0...15..9..1....3..4..3....9.15..7 %e A223600 .11..3..2....4..3..4...10..8.10....0..7..0...11..9.15....5..4..5...13.15..9 %Y A223600 Cf. A223599. %K A223600 nonn %O A223600 1,1 %A A223600 _R. H. Hardin_, Mar 23 2013