1,2

Diagonal of A272973.

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

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

Cf. A272973.

Sequence in context: A175365 A029769 A074590 * A105730 A213384 A005875

Adjacent sequences: A272963 A272964 A272965 * A272967 A272968 A272969

nonn

R. H. Hardin, May 11 2016

approved