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A209228 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.

%I A209228 #7 Jul 22 2025 21:41:24
%S A209228 28,784,896,1024,3456,11664,38232,125316,423384,1430416,4755296,
%T A209228 15808576,53167072,178810384,596712128,1991301376,6681462272,
%U A209228 22418473984,74937067264,250488238144,839514567296,2813643921664,9412504049664
%N A209228 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.
%C A209228 Row 7 of A209224
%H A209228 R. H. Hardin, <a href="/A209228/b209228.txt">Table of n, a(n) for n = 1..210</a>
%F A209228 Empirical: a(n) = 2*a(n-1) +6*a(n-3) +84*a(n-4) -128*a(n-5) -44*a(n-6) -144*a(n-7) -1872*a(n-8) +2504*a(n-9) +864*a(n-10) +1088*a(n-11) +16128*a(n-12) -19968*a(n-13) -5632*a(n-14) -2816*a(n-15) -57344*a(n-16) +66560*a(n-17) +11264*a(n-18) +4096*a(n-19) +77824*a(n-20) -83968*a(n-21) -8192*a(n-22) -32768*a(n-24) +32768*a(n-25) for n>28
%e A209228 Some solutions for n=4
%e A209228 ..1..0..1..1....1..1..1..1....0..0..1..1....0..0..1..1....1..0..1..1
%e A209228 ..0..0..1..1....0..1..1..0....0..0..1..1....1..1..1..1....0..1..1..1
%e A209228 ..1..1..0..0....1..0..0..1....1..1..0..0....1..1..0..0....1..1..0..0
%e A209228 ..1..1..1..0....1..0..0..1....1..1..1..1....0..0..1..1....1..0..0..1
%e A209228 ..0..0..1..1....0..1..1..0....0..0..1..1....1..1..1..1....0..0..1..1
%e A209228 ..1..1..0..1....1..1..1..0....1..1..0..0....1..1..0..0....0..1..1..0
%e A209228 ..1..1..0..0....1..0..0..1....1..1..0..0....0..0..1..1....1..1..0..0
%K A209228 nonn
%O A209228 1,1
%A A209228 _R. H. Hardin_ Mar 06 2012