A195276 Number of lower triangles of an n X n integer array with each element differing from all of its vertical and horizontal neighbors by 6 or less and triangles differing by a constant counted only once

1, 169, 248261, 3249312469, 383752106451389, 411207789366962687359, 4011033701337366560359871745

Offset

1,2

Comments

Column 6 of A195278

Links

Table of n, a(n) for n=1..7.

Example

Some solutions for n=5
...0...............0...............0...............0...............0
..-6.-1...........-1..3...........-3.-8............3..9...........-2.-7
.-10.-6.-8........-6.-1..3.........1.-5.-8........-1..5..5.........1.-1.-7
.-15-10.-6.-9.....-9.-4.-2.-2......2..1.-2..2......3..7..4..2......1..0.-1..2
.-17-14-12.-9.-8.-10.-8.-4.-2..3...2..4.-1.-4.-6...1..6..4..5..0...5.-1.-7.-2..4

Crossrefs

Sequence in context: A210087 A135824 A195219 * A013753 A013867 A074666

Adjacent sequences: A195273 A195274 A195275 * A195277 A195278 A195279

Keyword

nonn

Author

R. H. Hardin Sep 14 2011

Status

approved