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A207756 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically.

%I A207756 #7 Jul 22 2025 20:47:29
%S A207756 35,1225,7210,42436,147084,509796,1341606,3530641,7826035,17347225,
%T A207756 34169660,67305616,121583280,219632400,371285460,627652809,1006704699,
%U A207756 1614673489,2481460982,3813556516,5656542892,8390193604,12078020682
%N A207756 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically.
%C A207756 Row 7 of A207752
%H A207756 R. H. Hardin, <a href="/A207756/b207756.txt">Table of n, a(n) for n = 1..210</a>
%F A207756 Empirical: a(n) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)
%e A207756 Some solutions for n=4
%e A207756 ..0..0..0..0....1..0..0..0....1..0..1..0....0..0..0..0....1..0..1..0
%e A207756 ..0..1..0..1....0..0..0..0....1..1..0..1....1..1..1..1....1..0..0..0
%e A207756 ..0..0..0..0....1..0..0..0....1..1..1..1....0..0..0..0....1..0..1..0
%e A207756 ..0..1..0..1....0..0..0..0....0..1..0..0....1..1..1..1....1..0..0..0
%e A207756 ..0..1..0..0....1..0..0..0....1..1..1..1....1..0..1..0....1..0..1..0
%e A207756 ..0..1..0..1....0..0..0..0....1..0..0..0....0..1..0..1....0..0..0..0
%e A207756 ..0..1..0..0....1..0..0..0....1..1..1..1....1..0..1..0....1..0..1..0
%K A207756 nonn
%O A207756 1,1
%A A207756 _R. H. Hardin_ Feb 19 2012