A147357 Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0110-0110-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 2, 3, 8, 13, 22, 45, 113, 275, 994, 2604, 9935, 31457, 134870, 529162, 2763867, 12621629, 78239209, 410491794, 3050461822

Offset

1,8

Links

Table of n, a(n) for n=1..26.

Example

Maximal 8 X 8 example
.0.0.1.1.1.1.0.0
.0.0.0.1.1.0.0.0
.1.0.0.1.1.0.0.1
.1.1.1.0.0.1.1.1
.1.1.1.0.0.1.1.1
.1.0.0.1.1.0.0.1
.0.0.0.1.1.0.0.0
.0.0.1.1.1.1.0.0

Crossrefs

Sequence in context: A147329 A175148 A147417 * A004138 A213046 A262021

Adjacent sequences: A147354 A147355 A147356 * A147358 A147359 A147360

Keyword

nonn

Author

R. H. Hardin

Status

approved