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%I #5 Mar 31 2012 12:36:00
%S 50,5736,3436266,12900566348,276510402290782,35245029137091490532,
%T 26246732217663407375879655,115019923806287297509943176811916,
%U 2957519612846906106776158316962863659667
%N Number of (n+1)X(n+1) 0..2 arrays with no 2X2 subblock summing to less than 4
%C Diagonal of A184564
%e Some solutions for 3X3
%e ..2..2..2....1..2..0....2..0..2....2..0..2....1..2..2....2..2..0....2..1..2
%e ..2..2..2....2..1..1....1..2..2....1..2..1....2..1..1....2..1..2....2..2..2
%e ..2..0..1....0..2..2....0..2..2....0..2..1....0..1..2....2..1..1....1..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 17 2011