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%I #4 Nov 30 2014 20:14:43
%S 9,63,758,16911,666522,48781920,6424279907,1559013699145,
%T 686199785166132,553366441376509592,812147106821250119851,
%U 2177986074523549871596544,10645119952388702328957451736
%N Number of (n+1)X(n+1) 0..1 arrays with no 2X2 subblock having zero or two 1s
%C Diagonal of A251219
%e Some solutions for n=4
%e ..0..1..1..1..1....1..0..1..1..1....1..0..1..1..1....1..1..0..1..0
%e ..1..1..1..1..1....1..1..1..1..0....1..1..1..1..0....1..1..1..1..1
%e ..1..1..1..1..1....1..1..1..1..1....1..1..0..1..1....0..1..1..1..1
%e ..0..1..1..1..1....0..1..1..1..1....0..1..1..1..0....1..1..1..1..1
%e ..0..0..1..0..1....0..0..1..1..0....0..0..1..1..1....0..1..1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 30 2014