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A207484 Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically.

%I A207484 #7 Jul 22 2025 20:29:06
%S A207484 9,81,217,530,1459,3947,11306,32445,96201,286920,873201,2673027,
%T A207484 8288284,25824249,81128201,255825008,811028901,2578371055,8225731808,
%U A207484 26296176189,84258830581,270382678904,868986130961,2795785995547,9004226853968
%N A207484 Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically.
%C A207484 Column 4 of A207488
%H A207484 R. H. Hardin, <a href="/A207484/b207484.txt">Table of n, a(n) for n = 1..210</a>
%F A207484 Empirical: a(n) = 8*a(n-1) -5*a(n-2) -106*a(n-3) +209*a(n-4) +518*a(n-5) -1487*a(n-6) -1150*a(n-7) +4949*a(n-8) +938*a(n-9) -8999*a(n-10) +706*a(n-11) +9184*a(n-12) -2042*a(n-13) -5056*a(n-14) +1552*a(n-15) +1334*a(n-16) -472*a(n-17) -128*a(n-18) +48*a(n-19) for n>20
%e A207484 Some solutions for n=4
%e A207484 ..1..0..1..0....1..1..0..1....0..0..1..0....1..1..0..1....0..0..1..0
%e A207484 ..0..0..1..0....0..0..1..0....0..1..0..1....1..1..0..1....1..0..1..0
%e A207484 ..1..1..1..1....0..1..0..1....0..0..1..0....1..1..1..1....0..0..1..0
%e A207484 ..0..0..1..0....1..0..1..0....0..1..0..1....1..1..0..1....0..0..1..0
%K A207484 nonn
%O A207484 1,1
%A A207484 _R. H. Hardin_ Feb 18 2012