A147387 Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 10001-11111-00100 pattern in any orientation.

1, 1, 1, 1, 1, 1, 3, 9, 20, 57, 190, 629, 2776, 15917, 99291, 695261, 5658010, 52047047, 554192227, 6986434456, 103110572004, 1764252322607, 34869976082784

Offset

1,7

Links

Table of n, a(n) for n=1..23.

Example

Maximal 8 X 8 example
.0.0.0.0.0.1.1.0
.0.0.0.0.0.1.0.0
.0.0.0.0.1.1.0.0
.0.0.0.0.0.1.0.0
.0.0.1.0.0.1.1.0
.1.1.1.1.1.0.0.0
.1.0.0.0.1.0.0.0
.0.0.0.0.0.0.0.0

Crossrefs

Sequence in context: A147356 A147416 A078841 * A146267 A151420 A196294

Adjacent sequences: A147384 A147385 A147386 * A147388 A147389 A147390

Keyword

nonn

Author

R. H. Hardin

Status

approved