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A207850 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207850 #7 Jul 22 2025 20:53:07
%S A207850 42,1764,6216,35952,185136,1006572,5346600,28935984,154692048,
%T A207850 835671396,4480109592,24171724080,129787001904,699638944620,
%U A207850 3760020085080,20257347370848,108927000309120,586630343266884,3155460147857976
%N A207850 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207850 Row 7 of A207845
%H A207850 R. H. Hardin, <a href="/A207850/b207850.txt">Table of n, a(n) for n = 1..210</a>
%F A207850 Empirical: a(n) = 2*a(n-1) +40*a(n-2) -50*a(n-3) -511*a(n-4) +376*a(n-5) +2736*a(n-6) -1247*a(n-7) -7118*a(n-8) +2183*a(n-9) +9712*a(n-10) -2183*a(n-11) -7118*a(n-12) +1247*a(n-13) +2736*a(n-14) -376*a(n-15) -511*a(n-16) +50*a(n-17) +40*a(n-18) -2*a(n-19) -a(n-20) for n>21
%e A207850 Some solutions for n=4
%e A207850 ..0..1..0..1....1..0..1..0....1..0..1..1....1..1..1..1....0..1..1..1
%e A207850 ..1..0..1..0....1..0..1..1....1..1..0..1....1..0..1..0....1..0..1..0
%e A207850 ..0..1..0..1....0..1..0..0....0..1..0..0....0..1..0..0....0..1..0..1
%e A207850 ..0..1..0..1....1..0..1..1....1..0..1..0....1..1..1..1....0..1..1..1
%e A207850 ..1..0..1..0....0..1..1..0....0..1..0..1....1..0..1..1....1..0..1..0
%e A207850 ..1..1..1..1....1..1..0..1....0..1..1..1....0..1..0..0....1..1..0..1
%e A207850 ..0..1..0..1....1..0..1..0....1..0..1..0....0..1..1..0....0..1..0..0
%K A207850 nonn
%O A207850 1,1
%A A207850 _R. H. Hardin_ Feb 21 2012