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A207243 Number of 3Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically.

%I A207243 #7 Jul 22 2025 20:11:58
%S A207243 6,36,102,283,699,1526,3355,6888,13954,27816,54211,105147,201340,
%T A207243 382799,723838,1359688,2544322,4740623,8801291,16292518,30071783,
%U A207243 55371672,101727342,186506700,341316455,623552411,1137394900,2071676507
%N A207243 Number of 3Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically.
%C A207243 Row 3 of A207242
%H A207243 R. H. Hardin, <a href="/A207243/b207243.txt">Table of n, a(n) for n = 1..210</a>
%F A207243 Empirical: a(n) = 4*a(n-1) -3*a(n-2) -3*a(n-3) -4*a(n-4) +16*a(n-5) -8*a(n-6) +2*a(n-7) -8*a(n-8) +10*a(n-9) -14*a(n-10) +12*a(n-11) -4*a(n-12) +4*a(n-13) -5*a(n-14) +4*a(n-15) -3*a(n-16) +a(n-17)
%e A207243 Some solutions for n=4
%e A207243 ..0..1..0..1....1..0..1..0....1..1..1..1....0..0..1..0....0..0..1..0
%e A207243 ..1..0..0..1....1..0..1..0....1..1..0..1....0..1..0..0....1..1..1..1
%e A207243 ..1..1..0..0....0..0..1..0....1..0..1..0....0..1..0..0....1..1..1..1
%K A207243 nonn
%O A207243 1,1
%A A207243 _R. H. Hardin_ Feb 16 2012