A180751 Half the number of n X n binary arrays with each element equal to at least two neighbors.

0, 1, 1, 9, 86, 2986, 205020, 33329847, 11843513563, 9371551715962, 16360949033733903

Offset

1,4

Comments

Diagonal of A180760

Links

Table of n, a(n) for n=1..11.

Crossrefs

Sequence in context: A015581 A152261 A028339 * A266828 A100814 A055725

Adjacent sequences: A180748 A180749 A180750 * A180752 A180753 A180754

Keyword

nonn

Author

R. H. Hardin, Sep 20 2010

Status

approved