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%I #15 Sep 10 2019 03:18:31
%S 2,6,5,2,22,356,108,24,672,25056,4680,720,38160,2531520,342720,40320,
%T 3467520,358444800,38102400,3628800,460857600,68388364800,5987520000,
%U 479001600,84304281600,16979648716800,1264085222400,87178291200,20312541849600
%N Number of minimum dominating sets in the n X n white bishop graph.
%H Andrew Howroyd, <a href="/A323501/b323501.txt">Table of n, a(n) for n = 2..50</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MinimumDominatingSet.html">Minimum Dominating Set</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WhiteBishopGraph.html">White Bishop Graph</a>
%F From _Andrew Howroyd_, Sep 09 2019: (Start)
%F a(n) = (n/2)! * (n + 1)/2 for n mod 4 = 0;
%F a(n) = ((n-1)/2)! for n mod 4 = 1;
%F a(n) = (n/2-1)! * (n^2 + n + 2)/4 for n mod 4 = 2;
%F a(n) = ((n-3)/2)! * (n + 1)*(n^3 + n^2 - 6*n + 6)/16 for n mod 4 = 3.
%F (End)
%o (PARI) \\ See A289170 for DomSetCount, Bishop.
%o a(n)={Vec(DomSetCount(Bishop(n, 1), x + O(x^((n+3)\2))))[1]} \\ _Andrew Howroyd_, Sep 08 2019
%o (PARI) a(n)=(n\4*2)!*if(n%4<2, if(n%2==0, (n + 1)/2, 1), if(n%2==0, (n^2 + n + 2)/4, (n + 1)*(n^3 + n^2 - 6*n + 6)/16)); \\ _Andrew Howroyd_, Sep 09 2019
%Y Cf. A182333 (bishop graph), A323500 (black bishop graph).
%Y Cf. A287897, A289170, A303144.
%K nonn
%O 2,1
%A _Eric W. Weisstein_, Jan 16 2019
%E Offset corrected and terms a(11) and beyond from _Andrew Howroyd_, Sep 08 2019
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