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A195764
Number of triangular nXnXn 0..2 arrays with all row sums equal to the length of the row and all diagonal sums equal to the length of the respective diagonal
0
1, 1, 1, 3, 15, 135, 2889, 146559, 17742675, 5342155407
OFFSET
1,4
COMMENTS
Column 2 of A195768
EXAMPLE
Some solutions for n=6
.......1............1............1............1............1............1
......1.1..........1.1..........2.0..........0.2..........2.0..........0.2
.....1.0.2........1.0.2........1.1.1........2.1.0........1.0.2........2.0.1
....1.1.2.0......0.2.1.1......0.2.0.2......1.0.2.1......1.2.1.0......2.0.1.1
...1.2.0.1.1....2.2.0.1.0....1.1.1.1.1....1.1.1.1.1....0.1.0.2.2....0.1.2.2.0
..1.1.0.2.1.1..1.0.1.1.2.1..1.1.2.0.1.1..1.1.1.1.1.1..1.2.1.1.0.1..1.2.0.0.2.1
CROSSREFS
Sequence in context: A232699 A030539 A028362 * A113723 A113379 A267018
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 23 2011
STATUS
approved