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

1, 1, 1, 3, 15, 135, 2889, 146559, 17742675, 5342155407

Offset

1,4

Comments

Column 2 of A195768

Links

Table of n, a(n) for n=1..10.

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

Adjacent sequences: A195761 A195762 A195763 * A195765 A195766 A195767

Keyword

nonn

Author

R. H. Hardin Sep 23 2011

Status

approved