A147094 - OEIS

A147094

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1000-1000-1111 pattern in any orientation.

1, 1, 1, 3, 7, 15, 31, 73, 307, 1451, 6775, 33773, 192865, 1471507, 13382667, 137085697, 1565839497, 20450552451, 319414253795, 5882181538191, 126047394686961, 3114606848932875

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

OFFSET

1,4

LINKS

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

EXAMPLE

Maximal 8 X 8 example

.0.0.0.1.0.0.0.0

.0.0.0.1.0.1.0.0

.1.1.1.1.0.1.0.0

.0.0.0.0.0.1.0.1

.0.0.1.1.1.1.0.1

.0.0.0.0.0.0.0.1

.0.0.0.0.1.1.1.1

CROSSREFS

Sequence in context: A147235 A024876 A146598 * A326518 A147285 A147250

Adjacent sequences: A147091 A147092 A147093 * A147095 A147096 A147097

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 04 2008

STATUS

approved