A147409 - OEIS

A147409

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1001-1001-1111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 7, 13, 21, 31, 61, 147, 365, 1043, 3041, 10027, 33377, 115807, 406723, 1580475, 6700609

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OFFSET

1,10

LINKS

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

EXAMPLE

Maximal 10 X 10 example

.0.0.0.1.0.0.1.0.0.0

.0.0.0.1.1.1.1.0.0.0

.1.1.1.0.0.0.0.1.1.1

.0.0.1.0.0.0.0.1.0.0

.1.1.1.0.0.0.0.1.1.1

.0.0.0.1.1.1.1.0.0.0

.0.0.0.1.0.0.1.0.0.0

CROSSREFS

Sequence in context: A098577 A004136 A335865 * A147342 A172310 A357370

Adjacent sequences: A147406 A147407 A147408 * A147410 A147411 A147412

KEYWORD

nonn

AUTHOR

R. H. Hardin

STATUS

approved