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A207244 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically.

%I A207244 #7 Jul 22 2025 20:12:05
%S A207244 9,81,287,987,2884,7165,17929,40646,90602,196548,412733,859077,
%T A207244 1751887,3532169,7052859,13932019,27335037,53236611,103050502,
%U A207244 198448577,380245761,725544748,1379004108,2611731954,4930796893,9281596371
%N A207244 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically.
%C A207244 Row 4 of A207242
%H A207244 R. H. Hardin, <a href="/A207244/b207244.txt">Table of n, a(n) for n = 1..210</a>
%F A207244 Empirical: a(n) = 5*a(n-1) -4*a(n-2) -12*a(n-3) +3*a(n-4) +47*a(n-5) -17*a(n-6) -66*a(n-7) -9*a(n-8) +90*a(n-9) +2*a(n-10) -33*a(n-11) +a(n-12) -5*a(n-13) -44*a(n-14) +19*a(n-15) +52*a(n-16) -16*a(n-17) -7*a(n-18) -3*a(n-19) +a(n-20) -18*a(n-21) +17*a(n-22) -2*a(n-23) +2*a(n-24) -3*a(n-25) +3*a(n-26) -3*a(n-27) +a(n-28)
%e A207244 Some solutions for n=4
%e A207244 ..0..0..1..0....1..0..0..1....0..1..0..1....1..1..1..1....0..1..0..0
%e A207244 ..0..1..0..0....0..1..0..1....0..0..1..0....1..1..1..1....0..0..1..0
%e A207244 ..0..1..0..0....1..1..0..1....0..0..1..0....1..1..1..1....0..0..1..0
%e A207244 ..0..1..0..0....1..0..0..1....0..0..1..0....0..1..0..1....0..0..1..0
%K A207244 nonn
%O A207244 1,1
%A A207244 _R. H. Hardin_ Feb 16 2012