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A195894
Number of lower triangles of a 6X6 integer array with all row and column sums zero and all row and column sums of squares <= 2n^2
0
591, 90013, 4857647, 65530899, 584257875, 3204150229, 15120998539, 54574236425, 172034293523, 489664849531
OFFSET
1,1
COMMENTS
Row 6 of A195892
EXAMPLE
Some solutions for n=4
..0............0............0............0............0............0
.-4.4..........2-2..........4-4..........2-2..........2-2..........4-4
.-1-1.2.......-1-1.2.......-4.1.3........3.1-4.......-1.0.1.......-2-2.4
..1-3.3-1.....-1.1.1-1......0.1.2-3.....-3-2.4.1......3-2.0-1......1.2-3.0
..1-1-2.0.2....0.3-4-1.2....0.3-2.2-3...-2.1.0-2.3...-3.3.1-2.1...-2.2.0.1-1
..3.1-3.1-2.0..0-1.1.2-2.0..0-1-3.1.3.0..0.2.0.1-3.0.-1.1-2.3-1.0.-1.2-1-1.1.0
CROSSREFS
Sequence in context: A320713 A116170 A171724 * A263555 A156835 A129191
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 24 2011
STATUS
approved