A185537 1/6 the number of nX4 0..5 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.

6, 1155, 127570, 17526450, 2241330570, 295044602325, 38418831900875, 5024252800116630, 655951718326130130, 85695581922306489845, 11192649881286988768850, 1462013677990229903804335

Offset: 1

Author

R. H. Hardin Jan 30 2011

Keywords

• nonn

Comments

Column 4 of A185540

Examples

			Some solutions for 3X4 with a(1,1)=0
..0..5..5..4....0..2..5..5....0..0..2..4....0..1..2..2....0..0..0..2
..0..1..5..4....0..2..3..5....1..3..2..4....0..1..0..4....3..2..2..2
..1..1..3..3....2..2..3..3....1..3..4..4....5..5..0..4....3..5..5..5
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..48