A272966 - OEIS

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A272966

Number of n X n 0..1 arrays with exactly n+n-2 having value 1 and no three 1's forming an isosceles triangle.

0

1, 6, 12, 8, 4, 8, 4, 8

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Diagonal of A272973.

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

Some solutions for n=3

..1..1..0. .1..0..1. .0..0..1. .0..1..1. .0..1..1. .1..0..0. .1..0..0

..0..0..0. .1..0..1. .1..0..1. .0..0..0. .0..0..0. .1..0..0. .1..0..1

..1..1..0. .0..0..0. .1..0..0. .0..1..1. .1..1..0. .0..1..1. .0..0..1

CROSSREFS

Sequence in context: A175365 A029769 A074590 * A105730 A213384 A005875

Adjacent sequences: A272963 A272964 A272965 * A272967 A272968 A272969

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 11 2016

STATUS

approved