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%I #6 Feb 10 2015 07:47:19
%S 512,7212,89310,1016249,3486340,12820652,45398628,102538840,261881432,
%T 773696684,1940850378,4904675739,13916479182,35276177013
%N Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal sum plus antidiagonal median nondecreasing horizontally, vertically and ne-to-sw antidiagonally
%C Diagonal of A254020
%e Some solutions for n=3
%e ..0..0..1..0..0....0..0..1..1..0....0..0..0..1..0....0..1..1..1..1
%e ..0..1..1..1..0....0..0..0..0..0....0..0..0..0..0....1..0..0..0..1
%e ..1..0..0..1..1....1..1..1..1..1....1..0..0..1..1....0..1..1..1..1
%e ..1..1..1..1..0....0..0..1..1..0....1..0..1..1..1....0..1..1..1..1
%e ..1..1..0..1..1....1..1..0..0..1....1..1..1..1..1....0..1..1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 22 2015