A305505 Number of nXn 0..1 arrays with every element unequal to 2, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.

0, 3, 4, 346, 13314, 1126154, 235231504, 93092873891, 74276306711509

Offset

1,2

Comments

Diagonal of A305509.

Links

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

Example

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

Crossrefs

Cf. A305509.

Sequence in context: A348278 A348280 A304150 * A069970 A305169 A316759

Adjacent sequences: A305502 A305503 A305504 * A305506 A305507 A305508

Keyword

nonn

Author

R. H. Hardin, Jun 03 2018

Status

approved