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A195889
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 <=50
0
1, 1, 11, 671, 241221, 584257875
OFFSET
1,3
COMMENTS
Column 5 of A195892
EXAMPLE
Some solutions for n=4
..0........0........0........0........0........0........0........0
.-5.5.....-4.4......5-5.....-1.1.....-1.1.....-2.2.....-4.4......3-3
..5-1-4...-1.1.0....0.4-4....5-1-4....5-1-4....2-5.3....0-1.1....1-2.1
..0-4.4.0..5-5.0.0.-5.1.4.0.-4.0.4.0.-4.0.4.0..0.3-3.0..4-3-1.0.-4.5-1.0
CROSSREFS
Sequence in context: A201175 A211401 A036933 * A195519 A218716 A232355
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 24 2011
STATUS
approved