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A207001 Number of 4Xn 0..1 arrays avoiding 0 1 0 horizontally and 0 1 1 vertically.

%I A207001 #7 Jul 22 2025 19:55:37
%S A207001 12,144,1020,6612,45932,329734,2346621,16555996,116824836,825944298,
%T A207001 5841333854,41296838816,291917220483,2063599965447,14588455360112,
%U A207001 103131522271050,729070029502689,5154026289337418,36435512589728099
%N A207001 Number of 4Xn 0..1 arrays avoiding 0 1 0 horizontally and 0 1 1 vertically.
%C A207001 Row 4 of A207000
%H A207001 R. H. Hardin, <a href="/A207001/b207001.txt">Table of n, a(n) for n = 1..210</a>
%F A207001 Empirical: a(n) = 12*a(n-1) -66*a(n-2) +302*a(n-3) -765*a(n-4) +1446*a(n-5) -323*a(n-6) -5615*a(n-7) +13155*a(n-8) -14780*a(n-9) -33360*a(n-10) +114407*a(n-11) -55387*a(n-12) -144528*a(n-13) +485368*a(n-14) -387119*a(n-15) -1329517*a(n-16) +1697828*a(n-17) +2024417*a(n-18) -2840081*a(n-19) -1775201*a(n-20) +2598810*a(n-21) +710729*a(n-22) -1248295*a(n-23) +112490*a(n-24) +169231*a(n-25) -221480*a(n-26) +97360*a(n-27) +61312*a(n-28) -26508*a(n-29) +917*a(n-30) -3775*a(n-31) -1940*a(n-32) +564*a(n-33) +66*a(n-34) +376*a(n-35) -3*a(n-36) -41*a(n-37) +9*a(n-38) -8*a(n-39) -a(n-40) +a(n-41)
%e A207001 Some solutions for n=4
%e A207001 ..1..1..0..0....1..0..0..1....1..0..0..1....1..1..0..1....1..0..1..1
%e A207001 ..0..1..1..1....0..0..0..0....1..1..0..0....0..0..1..1....0..0..0..1
%e A207001 ..1..1..0..0....1..0..1..1....1..0..1..1....0..0..0..1....1..0..1..1
%e A207001 ..0..1..1..1....0..0..0..0....1..1..0..0....0..1..1..1....0..0..0..1
%K A207001 nonn
%O A207001 1,1
%A A207001 _R. H. Hardin_ Feb 14 2012