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%I #5 Dec 18 2015 18:18:31
%S 2,16,240,4466,89630,1856100,39162020,840122330,18350758538,
%T 409124396540,9333564282142,218396645933584,5252293916506694
%N Number of n X n 0..1 arrays with rows and columns unimodal
%C Diagonal of A223620
%e Some solutions for n=4
%e ..1..1..0..0....0..1..0..0....0..0..0..0....1..0..0..0....0..1..1..0
%e ..1..1..0..0....1..1..0..0....0..1..0..0....1..1..0..0....0..1..1..0
%e ..1..1..0..0....0..1..0..0....0..1..1..0....1..1..1..1....0..1..1..0
%e ..0..0..0..1....0..0..1..1....0..1..1..0....1..1..1..0....0..1..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 24 2013