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A205748 Number of (n+1)X4 0..2 arrays with every 2X2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..2 introduced in row major order.

%I A205748 #7 Jul 22 2025 18:59:56
%S A205748 175,1074,8926,63838,507035,3797920,29561841,224378004,1731531322,
%T A205748 13218640560,101623450551,777700795868,5969371745835,45729619667448,
%U A205748 350767461372176,2688316203091256,20614685172668943,158022715770190920
%N A205748 Number of (n+1)X4 0..2 arrays with every 2X2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..2 introduced in row major order.
%C A205748 Column 3 of A205753
%H A205748 R. H. Hardin, <a href="/A205748/b205748.txt">Table of n, a(n) for n = 1..210</a>
%F A205748 Empirical: a(n) = 54*a(n-2) +120*a(n-3) -417*a(n-4) -1856*a(n-5) -569*a(n-6) +11608*a(n-7) +19462*a(n-8) -37804*a(n-9) -97827*a(n-10) +69396*a(n-11) +253384*a(n-12) -49104*a(n-13) -366356*a(n-14) -46288*a(n-15) +244448*a(n-16) +127408*a(n-17) +41532*a(n-18) -58496*a(n-19) -119360*a(n-20) -44544*a(n-21) for n>22
%e A205748 Some solutions for n=4
%e A205748 ..0..1..0..2....0..1..1..0....0..1..0..2....0..0..1..0....0..1..2..0
%e A205748 ..2..2..0..1....1..1..0..0....2..0..1..0....0..1..1..1....2..0..1..2
%e A205748 ..2..0..0..1....0..2..2..1....1..0..2..2....0..2..0..2....0..0..1..1
%e A205748 ..2..1..2..1....2..2..1..1....0..0..2..0....2..2..0..0....1..2..2..0
%e A205748 ..1..2..0..2....1..0..0..2....2..1..1..1....0..1..1..2....1..2..0..0
%K A205748 nonn
%O A205748 1,1
%A A205748 _R. H. Hardin_ Jan 30 2012