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%I #9 Dec 26 2023 23:43:38
%S 0,169,57232,57786977,209465946364,2887918719647127,
%T 155235965473002555740,32957218604273839302036966,
%U 27844021444678245712948156418880,94058066849689205593691581157744700550
%N Number of (n+1) X (n+1) 0..2 arrays containing all values 0..2 with every 2 X 2 subblock having one or two distinct values, and new values 0..2 introduced in row major order.
%C Diagonal of A210095.
%e Some solutions for n=4
%e ..0..1..0..2..1....0..0..0..1..2....0..1..2..0..1....0..0..0..0..0
%e ..0..1..0..2..1....0..1..0..1..2....0..1..2..0..1....0..0..1..0..1
%e ..0..0..0..2..2....0..0..0..1..2....0..1..2..0..1....1..1..1..0..0
%e ..0..0..0..2..2....1..0..1..1..1....1..1..2..0..1....1..2..1..1..1
%e ..0..1..0..2..0....0..1..1..2..1....2..1..2..0..0....1..2..1..2..2
%Y Cf. A210095.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 17 2012