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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

Cf. A272973.

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

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Last modified September 23 05:28 EDT 2021. Contains 347609 sequences. (Running on oeis4.)