A252937 Number of nX7 nonnegative integer arrays with upper left 0 and every value within 3 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down.

42, 329, 3016, 30818, 320270, 2952734, 21312696, 113154831, 440052087, 1302939451, 3104860285, 6297578921, 11347942213, 18725672417, 28900783485, 42343299609, 59523244981, 80910643793, 106975520237, 138187898505

Offset: 1

Author

R. H. Hardin, Dec 24 2014

Keywords

• nonn

Comments

Column 7 of A252938

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (235012096/3)*n^3 - 1891478912*n^2 + (46791365972/3)*n - 43861899175 for n>12