A272962 Number of nX5 0..1 arrays with exactly n+5-1 having value 1 and no three 1s forming an isosceles right triangle.

1, 1, 9, 8, 12, 58, 367, 1952, 10854, 28952, 111036, 509073, 1987399, 7893688, 31529461, 127809627, 503908003, 2046633068, 8290122978, 32995116709, 132715051945, 535961114544

Offset

1,3

Comments

Column 5 of A272965.

Links

Table of n, a(n) for n=1..22.

Example

Some solutions for n=6
..1..1..0..0..1. .1..1..0..1..0. .1..1..0..0..1. .1..1..1..0..0
..0..0..1..0..0. .0..0..0..1..0. .0..0..1..0..0. .0..0..0..1..0
..0..0..0..0..1. .0..0..0..0..1. .1..0..0..0..0. .0..0..0..0..1
..1..0..0..0..0. .0..0..0..0..1. .1..0..0..0..0. .1..0..0..0..1
..0..0..1..0..0. .0..0..0..1..0. .0..0..1..0..0. .0..0..0..0..1
..1..0..0..1..1. .1..1..0..1..0. .1..1..0..0..1. .1..0..0..0..1

Crossrefs

Cf. A272965.

Sequence in context: A343765 A019327 A004450 * A137392 A307639 A231483

Adjacent sequences: A272959 A272960 A272961 * A272963 A272964 A272965

Keyword

nonn

Author

R. H. Hardin, May 11 2016

Status

approved