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%I #7 Apr 23 2021 11:36:27
%S 63,600,3125,11766,53350,196974,660654
%N 1/36 the number of (n+2) X (n+2) 0..2 arrays with each 3 X 3 subblock containing two of one value, two of another, and five of the last.
%C Diagonal of A184457.
%e Some solutions with a(1,1)=0 for 4 X 4
%e ..0..0..0..0....0..1..1..0....0..0..2..0....0..1..0..0....0..1..2..0
%e ..0..0..1..0....2..1..2..2....0..1..2..0....0..0..2..0....1..0..0..2
%e ..1..2..2..1....1..1..0..1....0..0..1..0....1..2..0..1....2..0..0..1
%e ..1..1..1..1....0..1..1..0....0..0..2..0....0..1..0..0....2..0..1..2
%Y Cf. A184457.
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 14 2011