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%I #3 Mar 31 2012 12:35:49
%S 1,3,17,227,6743,454385,69050253,23720149995,18403310404291,
%T 32260116141540213,127750070550172845235,1142905840646183024996181,
%U 23099457587377397021217958619,1054727887880873003123899368746005
%N Number of nX(n+1) binary matrices with no initial bit string in any row or column divisible by 4
%C Superdiagonal 1 of A181031
%H R. H. Hardin, <a href="/A181032/b181032.txt">Table of n, a(n) for n=1..22</a>
%e Some solutions for 4X5
%e ..1..1..1..1..1....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
%e ..1..0..1..0..1....1..0..1..0..1....1..0..1..0..1....1..0..1..0..1
%e ..1..1..0..1..0....1..1..0..1..0....1..1..0..1..0....1..1..0..1..0
%e ..1..0..1..0..1....1..0..1..1..1....1..1..1..0..1....1..1..1..1..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 30 2010