A202918 Number of n X n nonnegative integer arrays with each row and column increasing from zero by 0, 1, 2 or 3.

1, 4, 90, 11016, 7083180, 23491810780, 398328574277322, 34356415364024198698, 15026792073190842661982128, 33259034071925704355191308972010

Offset

1,2

Links

Table of n, a(n) for n=1..10.

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

Adjacent sequences: A202915 A202916 A202917 * A202919 A202920 A202921

Keyword

nonn

Author

R. H. Hardin, Dec 26 2011

Status

approved