A147491 - OEIS

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A147491

Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 11101-10111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 25, 25, 137, 137, 521, 521, 6501, 6501, 70441, 70441, 694381, 694381, 20946853, 20946853, 656540805

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

OFFSET

1,11

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

Maximal 11 X 11 example

.1.1.0.1.1.0.1.1.0.1.1

.0.1.0.1.0.0.0.1.0.1.0

.1.1.0.1.1.0.1.1.0.1.1

.1.0.0.0.1.0.1.0.0.0.1

.1.1.0.1.1.0.1.1.0.1.1

.0.0.0.0.0.0.0.0.0.0.0

.1.1.0.1.1.0.1.1.0.1.1

.1.0.0.0.1.0.1.0.0.0.1

.1.1.0.1.1.0.1.1.0.1.1

.0.1.0.1.0.0.0.1.0.1.0

.1.1.0.1.1.0.1.1.0.1.1

CROSSREFS

Sequence in context: A323522 A040601 A022359 * A147507 A146865 A146740

Adjacent sequences: A147488 A147489 A147490 * A147492 A147493 A147494

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved