A194774 Number of lower triangles of an (n+6)X(n+6) 0..4 array with new values introduced in row major order 0..4 and no element unequal to more than one horizontal or vertical neighbor.

268, 672, 1736, 4464, 11686, 30608, 80961, 214469, 570921, 1521287, 4061881, 10847647, 28982750, 77406210, 206655490, 551301206, 1469565060, 3913609398, 10412354243, 27674510615, 73480819187, 194908131709, 516485443463

Offset: 1

Author

R. H. Hardin Sep 02 2011

Keywords

• nonn

Comments

Column 4 of A194778

Examples

			All solutions for 7X7 including a 4
..0..............0..............0
..1.1............1.1............1.1
..1.1.2..........1.1.1..........1.1.1
..1.1.2.2........2.2.2.2........2.2.2.2
..1.1.2.2.3......2.2.2.2.2......2.2.2.2.3
..1.1.2.2.3.3....3.3.3.3.3.3....2.2.2.2.3.3
..1.1.2.2.3.3.4..3.3.3.3.3.3.4..2.2.2.2.3.3.4
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..24