A146441 - OEIS

A146441

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 3, 9, 19, 39, 119, 357, 921, 3063, 15421, 82217, 416323, 2370803, 16101191, 113312875, 843888839, 7373458463, 76576709025

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

OFFSET

1,8

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

Maximal 8 X 8 example

.0.1.1.1.0.0.0.0

.1.0.0.1.0.0.0.0

.1.0.0.1.1.0.0.0

.1.1.1.0.0.1.0.0

.0.0.1.0.0.1.1.1

.0.0.0.1.1.0.0.1

.0.0.0.0.1.0.0.1

.0.0.0.0.1.1.1.0

CROSSREFS

Sequence in context: A327381 A146819 A147213 * A147341 A208972 A307541

Adjacent sequences: A146438 A146439 A146440 * A146442 A146443 A146444

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved