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A268773 Number of nX7 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

%I A268773 #4 Feb 13 2016 08:27:33
%S A268773 576,1456,17000,198114,2258084,24222418,255353744,2624246370,
%T A268773 26623649020,266457432340,2642221357236,25977398801092,
%U A268773 253689171829452,2462722401530246,23787359898720204,228742960985861366
%N A268773 Number of nX7 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
%C A268773 Column 7 of A268774.
%H A268773 R. H. Hardin, <a href="/A268773/b268773.txt">Table of n, a(n) for n = 1..210</a>
%F A268773 Empirical: a(n) = 12*a(n-1) +64*a(n-2) -942*a(n-3) -1476*a(n-4) +26868*a(n-5) +2249*a(n-6) -376788*a(n-7) +333472*a(n-8) +2686292*a(n-9) -4376424*a(n-10) -8985248*a(n-11) +21881197*a(n-12) +12658940*a(n-13) -55768960*a(n-14) +923990*a(n-15) +80699088*a(n-16) -25850884*a(n-17) -69171189*a(n-18) +34934900*a(n-19) +34833816*a(n-20) -22502076*a(n-21) -9502460*a(n-22) +7752808*a(n-23) +1023260*a(n-24) -1356480*a(n-25) +55136*a(n-26) +94080*a(n-27) -14400*a(n-28) for n>30
%e A268773 Some solutions for n=4
%e A268773 ..0..0..0..0..0..0..0. .0..0..0..0..1..0..0. .0..0..1..0..0..0..1
%e A268773 ..0..1..0..0..0..1..0. .0..0..0..0..0..0..1. .0..0..0..0..0..1..0
%e A268773 ..0..0..1..0..0..0..0. .1..0..0..0..0..0..0. .0..0..0..0..0..0..0
%e A268773 ..0..0..0..0..1..0..0. .1..0..1..0..0..0..1. .0..0..1..0..0..0..1
%Y A268773 Cf. A268774.
%K A268773 nonn
%O A268773 1,1
%A A268773 _R. H. Hardin_, Feb 13 2016