A195273 Number of lower triangles of an n X n integer array with each element differing from all of its vertical and horizontal neighbors by 3 or less and triangles differing by a constant counted only once

1, 49, 11319, 12608631, 68604760497, 1833160598134397, 241338657495589799523, 156865927758847103008175635, 504091149328239931994947830412175

Offset

1,2

Comments

Column 3 of A195278

Links

Table of n, a(n) for n=1..9.

Example

Some solutions for n=5
...0...............0...............0...............0...............0
...3..4...........-2..0............2..4............1..2...........-3.-1
...2..5..3........-3..0..3.........3..6..5.........0.-1.-1........-5.-2..1
...0..2..2..2......0..0..0.-1......6..3..6..6......0..2..1..3.....-2..1..3..5
...0..2..5..2..4..-3.-2.-3.-2.-1...6..5..6..8..9..-1..2..1..0.-3..-4.-2..0..2..1

Crossrefs

Sequence in context: A187406 A094199 A194023 * A222459 A145251 A202991

Adjacent sequences: A195270 A195271 A195272 * A195274 A195275 A195276

Keyword

nonn

Author

R. H. Hardin Sep 14 2011

Status

approved