A213960 Number of n X n 0..6 matrices with row and column i=1..n having sum <= i*6.
7, 980, 3323712, 256652587891, 447939229940051654, 17583943206407091985366455
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..2..3..0....1..2..0..0....2..3..0..0....1..1..3..0....5..0..0..1 ..0..5..5..0....1..4..0..1....0..3..1..5....1..1..6..0....1..0..1..4 ..5..0..3..6....1..5..3..3....0..3..4..4....4..4..1..0....0..1..3..4 ..0..0..4..5....0..0..1..0....3..0..4..1....0..5..2..5....0..4..6..6
Crossrefs
Cf. A213962.
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