A252813 Number of n X n nonnegative integer arrays with upper left 0 and every value within 2 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down

1, 6, 63, 684, 7564, 86724, 1033761, 12755742, 161986236, 2106102800, 27918827562, 376114207132, 5136290930902, 70961672284626, 990271326335611, 13940676825684808, 197768062909075426, 2824828311338844486

Offset

1,2

Comments

Diagonal of A252820

Links

R. H. Hardin, Table of n, a(n) for n = 1..40

Example

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

Crossrefs

Sequence in context: A134112 A071588 A001261 * A346581 A210987 A341376

Adjacent sequences: A252810 A252811 A252812 * A252814 A252815 A252816

Keyword

nonn

Author

R. H. Hardin, Dec 22 2014

Status

approved