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A202918
Number of n X n nonnegative integer arrays with each row and column increasing from zero by 0, 1, 2 or 3.
0
1, 4, 90, 11016, 7083180, 23491810780, 398328574277322, 34356415364024198698, 15026792073190842661982128, 33259034071925704355191308972010
OFFSET
1,2
EXAMPLE
Some solutions for n=4
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..1..2..3....0..0..2..2....0..0..3..3....0..0..2..2....0..0..0..1
..0..1..4..6....0..3..4..4....0..1..3..4....0..0..2..4....0..0..0..2
..0..3..4..7....0..3..4..7....0..1..4..7....0..1..4..6....0..0..2..3
CROSSREFS
Diagonal of A202924.
Sequence in context: A362603 A274056 A339987 * A146506 A202575 A201721
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2011
STATUS
approved