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A207019 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A207019 #9 Jul 22 2025 19:57:00
%S A207019 2,16,90,558,3315,16038,95900,492932,2542374,14009768,70576726,
%T A207019 371721351,1947251540,9924535935,51877222492,266862076008,
%U A207019 1370454630930,7087023247175,36312119188998,186625648529320,958786992765737
%N A207019 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A207019 Diagonal of A207024
%H A207019 R. H. Hardin, <a href="/A207019/b207019.txt">Table of n, a(n) for n = 1..31</a>
%e A207019 Some solutions for n=4
%e A207019 ..1..1..0..0....1..1..1..1....1..1..0..0....1..1..0..0....1..0..1..0
%e A207019 ..1..1..0..1....1..1..1..1....1..1..0..0....0..0..1..0....0..1..0..0
%e A207019 ..1..0..0..1....1..1..0..1....0..1..0..0....0..0..1..0....0..1..0..0
%e A207019 ..1..0..0..1....0..1..0..1....0..1..0..0....0..0..1..0....0..1..0..0
%K A207019 nonn
%O A207019 1,1
%A A207019 _R. H. Hardin_ Feb 14 2012