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A207878 Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 0 and 1 1 1 vertically.

%I A207878 #7 Jul 22 2025 20:54:57
%S A207878 28,784,1488,4200,8892,24952,51696,136490,313524,741944,1781472,
%T A207878 4256398,10168008,23945116,57760744,138028240,325742600,781955124,
%U A207878 1868173840,4441180174,10581963516,25315989248,60356380176,143569382950
%N A207878 Number of nX7 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 0 and 1 1 1 vertically.
%C A207878 Column 7 of A207879
%H A207878 R. H. Hardin, <a href="/A207878/b207878.txt">Table of n, a(n) for n = 1..210</a>
%F A207878 Empirical: a(n) = 2*a(n-2) +16*a(n-3) +9*a(n-4) -30*a(n-5) -124*a(n-6) -40*a(n-7) +210*a(n-8) +544*a(n-9) +116*a(n-10) -950*a(n-11) -1335*a(n-12) -420*a(n-13) +2586*a(n-14) +2672*a(n-15) +1600*a(n-16) -5088*a(n-17) -5011*a(n-18) -2288*a(n-19) +4642*a(n-20) +9096*a(n-21) +3040*a(n-22) -912*a(n-23) -10304*a(n-24) -6144*a(n-25) -436*a(n-26) +4768*a(n-27) +6648*a(n-28) +1728*a(n-29) -528*a(n-30) -3456*a(n-31) -2016*a(n-32) +1152*a(n-34) for n>40
%e A207878 Some solutions for n=4
%e A207878 ..1..0..0..1..0..0..1....1..1..0..0..1..0..0....0..1..0..0..1..0..0
%e A207878 ..0..1..0..0..1..1..0....1..1..1..0..0..1..0....1..0..0..1..0..0..1
%e A207878 ..0..1..0..0..1..1..1....0..0..1..0..0..1..0....1..0..0..1..1..1..1
%e A207878 ..1..0..0..1..0..0..1....1..1..0..0..1..0..0....0..1..0..0..1..1..0
%K A207878 nonn
%O A207878 1,1
%A A207878 _R. H. Hardin_ Feb 21 2012