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%I #6 Dec 18 2015 18:17:56
%S 1,1,2,12,304,44976,51871384,600608922384,87357442179208880,
%T 194354337721367202187520
%N Number of n X n nonnegative integer arrays with each row and column an ascent sequence (interior element no greater than one plus up-steps preceding it) and the lower right element equal to n-1
%C Diagonal of A202735
%e Some solutions for n=4
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e ..0..1..1..1....0..0..1..1....0..0..0..1....0..1..1..1....0..0..1..1
%e ..0..1..0..2....0..1..1..2....0..1..1..2....0..0..1..2....0..1..0..2
%e ..0..1..2..3....0..1..2..3....0..1..2..3....0..1..2..3....0..1..2..3
%K nonn
%O 1,3
%A _R. H. Hardin_ Dec 23 2011
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