A146175 - OEIS

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A146175

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 110-100-111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 5, 13, 25, 45, 121, 385, 1395, 5901, 28053, 137719, 714777, 4090907, 28017605, 214429525, 1879119265, 18054271787, 200571323617

(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

.0.0.0.1.1.1.0.0

.0.0.0.1.0.1.0.0

.0.0.0.1.0.0.1.1

.1.1.1.0.0.0.0.1

.1.0.0.0.0.1.1.1

.1.1.0.0.1.0.0.0

.0.0.1.0.1.0.0.0

.0.0.1.1.1.0.0.0

CROSSREFS

Sequence in context: A269713 A196069 A147182 * A146851 A146260 A147166

Adjacent sequences: A146172 A146173 A146174 * A146176 A146177 A146178

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 27 2008

STATUS

approved