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A268891 Number of 6Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

%I A268891 #4 Feb 15 2016 11:37:54
%S A268891 0,744,12252,236960,3596174,55491832,800733668,11458879568,
%T A268891 159796058742,2205638713335,30049236232518,406011322471540,
%U A268891 5441799029248756,72482603197808516,960023683579703110,12655255863840772464
%N A268891 Number of 6Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.
%C A268891 Row 6 of A268886.
%H A268891 R. H. Hardin, <a href="/A268891/b268891.txt">Table of n, a(n) for n = 1..210</a>
%F A268891 Empirical: a(n) = 2*a(n-1) +237*a(n-2) +556*a(n-3) -17745*a(n-4) -102122*a(n-5) +202421*a(n-6) +2379616*a(n-7) -22987*a(n-8) -27364786*a(n-9) -13031593*a(n-10) +199889692*a(n-11) +91121845*a(n-12) -1012462462*a(n-13) -190133151*a(n-14) +3595273076*a(n-15) -642988498*a(n-16) -8640634728*a(n-17) +4929067410*a(n-18) +12985931924*a(n-19) -13174973746*a(n-20) -9991379232*a(n-21) +18252268246*a(n-22) +272964868*a(n-23) -13058804606*a(n-24) +5323457016*a(n-25) +4041105222*a(n-26) -3401387484*a(n-27) -210272991*a(n-28) +912442186*a(n-29) -169777035*a(n-30) -118543140*a(n-31) +43493135*a(n-32) +6734614*a(n-33) -4652195*a(n-34) -21632*a(n-35) +259061*a(n-36) -13682*a(n-37) -7961*a(n-38) +524*a(n-39) +133*a(n-40) -6*a(n-41) -a(n-42)
%e A268891 Some solutions for n=3
%e A268891 ..1..0..0. .0..1..0. .1..0..1. .1..0..1. .1..0..1. .1..0..0. .0..0..1
%e A268891 ..0..1..0. .0..0..0. .0..1..0. .1..0..1. .1..0..0. .0..1..0. .1..0..0
%e A268891 ..0..0..1. .1..0..1. .0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..1..1
%e A268891 ..0..0..1. .1..0..0. .0..0..1. .1..1..0. .1..0..1. .0..1..0. .0..0..1
%e A268891 ..1..0..1. .1..1..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0
%e A268891 ..0..1..0. .0..0..1. .0..0..0. .1..0..1. .1..1..0. .0..1..1. .0..0..0
%Y A268891 Cf. A268886.
%K A268891 nonn
%O A268891 1,2
%A A268891 _R. H. Hardin_, Feb 15 2016