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 A187384 #10 Apr 24 2018 08:47:02 %S A187384 0,0,0,280,3792,17052,44464,92628,159328,245946,350386,472648,612732, %T A187384 770638,946366,1139916,1351288,1580482,1827498,2092336,2374996, %U A187384 2675478,2993782,3329908,3683856,4055626,4445218,4852632,5277868,5720926,6181806 %N A187384 Number of 10-step S, NW and NE-moving king's tours on an n X n board summed over all starting positions. %C A187384 Row 10 of A187377. %H A187384 R. H. Hardin, <a href="/A187384/b187384.txt">Table of n, a(n) for n = 1..50</a> %F A187384 Empirical: a(n) = 8911*n^2 - 82691*n + 181756 for n>8. %F A187384 Conjectures from _Colin Barker_, Apr 24 2018: (Start) %F A187384 G.f.: 2*x^4*(140 + 1476*x + 3258*x^2 + 2202*x^3 + 3300*x^4 - 1108*x^5 + 691*x^6 - 1048*x^7) / (1 - x)^3. %F A187384 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>11. %F A187384 (End) %Y A187384 Cf. A187377. %K A187384 nonn %O A187384 1,4 %A A187384 _R. H. Hardin_, Mar 09 2011