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%I #6 Apr 21 2020 12:46:24
%S 1,9,80,656,4180,68080,1643372,58423188,3045734096,235680645520,
%T 26923774835716,4558306996574952
%N Number of n X n 0..2 arrays with no element equal to any value at offset (-2,-1), (-2,0) or (-1,-1) and new values introduced in order 0..2.
%C Diagonal of A275504.
%e Some solutions for n=4
%e ..0..0..0..1. .0..1..2..2. .0..0..0..0. .0..1..2..2. .0..1..2..1
%e ..2..1..1..1. .0..2..2..0. .0..1..1..1. .1..1..2..0. .0..1..2..0
%e ..2..1..2..2. .2..2..0..1. .1..1..2..2. .1..2..0..0. .1..2..0..0
%e ..0..0..0..0. .2..1..0..1. .2..2..2..0. .2..0..0..1. .1..2..0..1
%Y Cf. A275504.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jul 30 2016