A195891 - OEIS

A195891

Number of lower triangles of an n X n integer array with all row and column sums zero and all row and column sums of squares <=98

1, 1, 15, 1695, 1686561, 15120998539

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OFFSET

1,3

COMMENTS

Column 7 of A195892

LINKS

EXAMPLE

Some solutions for n=4

..0........0........0........0........0........0........0........0

.-3.3.....-3.3......2-2.....-5.5......2-2.....-3.3......1-1......5-5

..5.1-6....7.0-7...-5.6-1....7.0-7...-3.6-3...-3-2.5....4-4.0....0.7-7

.-2-4.6.0.-4-3.7.0..3-4.1.0.-2-5.7.0..1-4.3.0..6-1-5.0.-5.5.0.0.-5-2.7.0

CROSSREFS

KEYWORD

nonn

AUTHOR

STATUS

approved