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A207124 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

%I A207124 #7 Jul 22 2025 20:03:19
%S A207124 9,81,289,1024,4096,14161,45796,150544,481636,1493284,4601025,
%T A207124 14055001,42380100,126900225,378108025,1119906225,3301766521,
%U A207124 9702250000,28419216400,83012558161,241951836996,703860593296,2044150748644
%N A207124 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.
%C A207124 Row 4 of A207123
%H A207124 R. H. Hardin, <a href="/A207124/b207124.txt">Table of n, a(n) for n = 1..210</a>
%F A207124 Empirical: a(n) = 6*a(n-1) -12*a(n-2) +30*a(n-3) -105*a(n-4) +140*a(n-5) -191*a(n-6) +637*a(n-7) -525*a(n-8) +374*a(n-9) -2132*a(n-10) +851*a(n-11) -82*a(n-12) +4997*a(n-13) -364*a(n-14) -761*a(n-15) -7828*a(n-16) -1358*a(n-17) +1552*a(n-18) +7812*a(n-19) +2336*a(n-20) -1168*a(n-21) -4944*a(n-22) -1472*a(n-23) +512*a(n-24) +1632*a(n-25) +448*a(n-26) -128*a(n-27) -256*a(n-28)
%e A207124 Some solutions for n=4
%e A207124 ..0..0..0..0....1..1..1..1....0..0..0..0....1..0..0..0....0..1..1..0
%e A207124 ..0..1..1..0....1..1..1..1....0..1..1..1....1..0..0..0....1..0..1..1
%e A207124 ..0..0..0..0....1..1..1..1....0..0..0..0....1..0..0..0....0..0..0..0
%e A207124 ..0..0..0..0....1..1..1..0....0..1..1..1....0..0..0..0....1..0..1..1
%K A207124 nonn
%O A207124 1,1
%A A207124 _R. H. Hardin_ Feb 15 2012