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 A286870 #17 Feb 16 2025 08:33:45 %S A286870 2,3,3,5,5,5,9,11,11,9,15,25,43,25,15,26,51,133,133,51,26,44,113,463, %T A286870 647,463,113,44,76,235,1493,2945,2945,1493,235,76,130,521,5011,14217, %U A286870 22049,14217,5011,521,130,223,1107,16659,65627,147672,147672,65627,16659,1107,223 %N A286870 Array read by antidiagonals: T(m,n) = number of irredundant sets in the m X n king graph. %H A286870 Andrew Howroyd, <a href="/A286870/b286870.txt">Table of n, a(n) for n = 1..153</a> %H A286870 Matthew D. Kearse and Peter B. Gibbons, <a href="http://hdl.handle.net/2292/3642">Computational Methods and New Results for Chessboard Problems</a>, CDMTCS Research Reports CDMTCS-133 (2000). %H A286870 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KingGraph.html">King Graph</a> %H A286870 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IrredundantSet.html">Irredundant Set</a> %e A286870 Array begins: %e A286870 ==================================================================== %e A286870 m\n| 1 2 3 4 5 6 7 8 %e A286870 ---|---------------------------------------------------------------- %e A286870 1 | 2 3 5 9 15 26 44 76... %e A286870 2 | 3 5 11 25 51 113 235 521... %e A286870 3 | 5 11 43 133 463 1493 5011 16659... %e A286870 4 | 9 25 133 647 2945 14217 65627 322163... %e A286870 5 | 15 51 463 2945 22049 147672 1043127 7365740... %e A286870 6 | 26 113 1493 14217 147672 1455385 14656628 151865727... %e A286870 7 | 44 235 5011 65627 1043127 14656628 218691097 3287831848... %e A286870 8 | 76 521 16659 322163 7365740 151865727 3287831848 72877697369... %e A286870 ... %Y A286870 Row 1 is A286887. %Y A286870 Main diagonal is A286871. %Y A286870 Cf. A218663 (dominating sets), A286849 (minimal dominating sets). %Y A286870 Cf. A286868 (grid graph). %K A286870 nonn,tabl %O A286870 1,1 %A A286870 _Andrew Howroyd_, Aug 02 2017