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%I #8 Apr 23 2021 09:36:50
%S 1,25,32920,276550270,33466433693229,72614149907378126398,
%T 2637221656906543119366072476,1479737300994461631995281660020138894
%N Number of n X n 0..4 arrays with every nonzero element less than or equal to some NW, E or S neighbor.
%C Diagonal of A203550.
%e Some solutions for n=5
%e ..3..0..1..3..2....1..4..2..2..3....1..0..4..0..3....0..1..3..4..4
%e ..3..2..1..3..4....0..4..3..1..4....1..0..4..0..3....2..0..1..1..4
%e ..3..1..4..2..4....1..4..3..3..4....3..2..4..3..3....2..2..3..4..0
%e ..3..4..4..4..4....3..4..2..4..4....4..3..4..2..3....1..2..3..4..2
%e ..4..4..4..3..4....3..4..4..3..4....4..4..4..4..0....4..4..4..4..4
%Y Cf. A203550.
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 02 2012