A304127 Number of n X n 0..1 arrays with every element unequal to 0, 1, 3 or 6 king-move adjacent elements, with upper left element zero.

1, 5, 9, 44, 176, 651, 2945, 14708, 79188, 495071, 3628565, 29134749, 265855219, 2732640025, 30998016185, 398665350465

Offset

1,2

Comments

Diagonal of A304133.

Links

Table of n, a(n) for n=1..16.

Example

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

Crossrefs

Cf. A304133.

Sequence in context: A123822 A226065 A321718 * A220518 A145031 A121724

Adjacent sequences: A304124 A304125 A304126 * A304128 A304129 A304130

Keyword

nonn

Author

R. H. Hardin, May 07 2018

Status

approved