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%I #8 May 25 2024 23:49:55
%S 1,49,296814,17549687172,22732800433168401,915339495505231856501713
%N Number of n X n 0..6 arrays with every nonzero element less than or equal to some NW, E or S neighbor.
%C Diagonal of A203506.
%e Some solutions for n=5
%e ..6..6..5..2..2....5..4..6..5..2....1..3..6..0..6....5..3..1..3..5
%e ..3..6..5..0..6....5..3..6..6..6....5..2..6..2..6....5..3..4..1..5
%e ..0..0..2..4..6....5..1..1..3..6....5..3..6..2..6....5..1..4..0..6
%e ..3..5..0..6..6....5..5..3..2..0....5..6..6..6..6....5..0..6..6..6
%e ..5..5..5..0..6....4..4..3..2..0....2..5..4..5..6....5..5..2..4..6
%Y Cf. A203506.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 02 2012