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A211885
Number of lower triangular n X n arrays of integers 0 upwards introduced in row major order, with each element unique in its row and column, and containing the value n(n+1)/2-2
0
0, 2, 8, 26, 66, 141, 267, 463, 751
OFFSET
1,2
COMMENTS
Column 1 of A211888
EXAMPLE
Some solutions for n=4
..0........0........0........0........0........0........0........0
..1.2......1.2......1.2......1.2......1.0......1.2......1.2......1.2
..3.4.1....3.4.5....3.4.5....3.4.5....2.3.4....3.4.5....3.4.5....3.4.5
..5.6.7.8..6.7.8.9..6.7.3.8..2.6.7.8..5.6.7.8..6.7.8.3..6.3.7.8..6.7.8.1
CROSSREFS
Sequence in context: A100504 A327600 A099416 * A101696 A155861 A212140
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 24 2012
STATUS
approved