A304953 Number of n X n 0..1 arrays with every element unequal to 1, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero.

0, 7, 42, 496, 11282, 435964, 30361694, 3805684538, 844100991906

Offset

1,2

Comments

Diagonal of A304959.

Links

Table of n, a(n) for n=1..9.

Example

Some solutions for n=5
..0..1..1..1..0. .0..1..1..1..0. .0..1..1..1..0. .0..1..1..0..0
..0..0..1..1..1. .1..1..1..0..0. .0..0..1..1..1. .1..1..1..1..0
..0..1..1..1..1. .1..0..1..0..1. .1..0..1..0..0. .1..1..0..0..1
..0..0..1..1..0. .1..1..0..0..0. .0..0..0..1..0. .0..1..1..1..0
..1..0..1..1..1. .0..1..1..1..1. .1..1..1..1..0. .0..0..0..0..1

Crossrefs

Cf. A304959.

Sequence in context: A278571 A133669 A205340 * A293850 A202862 A229437

Adjacent sequences: A304950 A304951 A304952 * A304954 A304955 A304956

Keyword

nonn

Author

R. H. Hardin, May 22 2018

Status

approved