A269894 Number of n X n 0..6 arrays with some element plus some horizontally or vertically adjacent neighbor totalling six exactly once.

0, 840, 12377400, 3263186052840, 19179756370570398120, 2711366026130939117933480040, 9555836762886245973504760743477970440

Offset

1,2

Comments

Diagonal of A269902.

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Cf. A269902.

Sequence in context: A331650 A331652 A364179 * A252780 A364264 A362440

Adjacent sequences: A269891 A269892 A269893 * A269895 A269896 A269897

Keyword

nonn

Author

R. H. Hardin, Mar 07 2016

Status

approved