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%I #5 Dec 18 2015 18:17:38
%S 1,1,3,9,46,462,6253,132061,4611023,250827373,21305367718,
%T 2862744251998,605949209796465,201612254630124309
%N Half the number of n X n symmetric binary matrices with no element equal to a strict majority of its king-move neighbors
%e Some solutions for n=4 with a(1,1)=0
%e ..0..1..1..0....0..1..0..1....0..1..0..1....0..1..0..0....0..1..0..1
%e ..1..0..0..1....1..1..0..1....1..1..0..0....1..0..1..1....1..1..0..1
%e ..1..0..0..1....0..0..0..1....0..0..1..1....0..1..0..0....0..0..1..0
%e ..0..1..1..0....1..1..1..0....1..0..1..0....0..1..0..1....1..1..0..1
%K nonn
%O 1,3
%A _R. H. Hardin_ May 14 2011