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A166174
Number of nXnXn triangular nonnegative integer arrays with all sums of an element and its neighbors <= 2
0
1, 3, 10, 29, 207, 2052, 23591, 461028, 13080857, 509035046, 29707234283, 2523185644983, 307483024897755, 54719108015588143, 14151178622373819910, 5302079572065910774222
OFFSET
0,2
EXAMPLE
Some solutions for n=4
.....0........1........1........0........0........1........0........0...
....0.0......0.0......0.0......0.0......0.0......0.0......0.0......0.0..
...0.0.0....0.0.1....1.0.0....0.0.0....0.1.0....1.0.1....0.0.0....1.0.0.
..0.1.0.1..0.1.0.0..1.0.0.1..0.2.0.0..1.0.0.1..0.0.0.0..2.0.0.2..0.0.0.2
------
.....1........0........0........0........0........2........0........2...
....0.0......0.0......1.0......2.0......0.1......0.0......0.0......0.0..
...1.0.1....1.0.0....0.0.1....0.0.0....0.0.0....0.0.0....0.1.0....0.0.0.
..1.0.0.1..1.0.0.1..0.0.0.1..0.0.0.2..1.1.0.1..2.0.0.1..0.0.0.0..1.0.0.0
CROSSREFS
Sequence in context: A147062 A293155 A146384 * A376089 A365224 A365748
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 09 2009
STATUS
approved