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%I #5 Dec 18 2015 18:18:41
%S 3,7,22,109,753,6374,62205,676983,8026548,101907085,1368004992,
%T 19233435438,281169127711,4249797119751,66116288446463
%N Number of n X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing
%C Diagonal of A229445
%e Some solutions for n=4
%e ..0..2..2..2....0..2..2..2....0..2..2..2....0..0..0..0....1..1..1..1
%e ..1..0..2..2....1..0..0..2....1..0..0..2....1..1..1..1....2..2..2..2
%e ..1..1..0..0....2..1..1..0....1..1..1..0....1..1..1..1....2..2..2..2
%e ..2..1..0..0....2..1..1..1....2..1..1..0....2..2..2..2....2..2..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 23 2013
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