A172645 Number of n X n 0..2 arrays with row sums n and column sums n.

1, 3, 31, 2371, 1084851, 3680774301, 91358224634433, 17470072106054582211, 26088526624958727703324771, 310419652143758898175543447421953, 29785621316391113552729016416250323294253

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n=1..14

Crossrefs

Main diagonal of A334549.

Sequence in context: A144906 A081789 A066976 * A201604 A048562 A022499

Adjacent sequences: A172642 A172643 A172644 * A172646 A172647 A172648

Keyword

nonn

Author

R. H. Hardin, Feb 06 2010

Status

approved