A166180 Number of nXnXn triangular nonnegative integer arrays with all sums of an element and its neighbors <= 8

1, 9, 165, 3613, 534687, 215061366, 191732812341, 622888856402932

Offset

0,2

Links

Table of n, a(n) for n=0..7.

Example

Some solutions for n=4
.....1........2........4........0........2........4........4........6...
....0.2......0.3......0.0......4.3......0.1......1.0......1.2......0.0..
...1.2.2....1.1.2....1.0.2....0.0.0....0.1.2....2.1.2....0.0.1....2.0.0.
..1.0.1.1..2.0.1.0..7.0.0.0..2.0.1.1..3.1.1.0..3.0.1.1..1.1.0.1..3.0.0.1
------
.....0........0........3........3........1........0........3........8...
....1.1......3.1......1.3......2.0......0.4......0.2......0.1......0.0..
...3.1.2....0.0.2....0.1.0....0.2.1....0.1.0....1.3.0....1.0.3....0.0.0.
..0.0.0.1..3.1.0.0..2.1.0.0..3.1.0.0..6.0.1.0..1.1.1.0..2.1.1.1..2.1.1.1

Crossrefs

Sequence in context: A086759 A053130 A219074 * A004107 A180831 A361094

Adjacent sequences: A166177 A166178 A166179 * A166181 A166182 A166183

Keyword

nonn

Author

R. H. Hardin Oct 09 2009

Status

approved