A195280 Number of lower triangles of a 4X4 integer array with each element differing from all of its vertical and horizontal neighbors by n or less and triangles differing by a constant counted only once

6939, 626525, 12608631, 119743353, 724789395, 3249312469, 11755976175, 36215968241, 98454861067, 242177297229, 548894457959, 1162058315625, 2322243189891, 4416808121541, 8048123047903, 14125147709409, 23983914638075

Offset

1,1

Comments

Row 4 of A195278

Links

R. H. Hardin, Table of n, a(n) for n = 1..169

Formula

Empirical: a(n) = (49024/315)*n^9 + (24512/35)*n^8 + (457792/315)*n^7 + (81824/45)*n^6 + (67912/45)*n^5 + (38756/45)*n^4 + (11832/35)*n^3 + (27752/315)*n^2 + (1454/105)*n + 1

Example

Some solutions for n=5
...0............0............0............0............0............0
..-1.-2.........1..1.........5..3.........3..1........-1.-3.........3..4
..-6.-5.-6.....-2..2.-1......5..3..1......7..4..2......1..1.-2......0..4..1
..-2.-1.-1..1...3..6..2..0...1.-2..3..1...5..3.-2.-1..-2..2..1..1..-5..0..2..1

Crossrefs

Sequence in context: A004244 A253736 A004245 * A059462 A252432 A072870

Adjacent sequences: A195277 A195278 A195279 * A195281 A195282 A195283

Keyword

nonn

Author

R. H. Hardin Sep 14 2011

Status

approved