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A180751
Half the number of n X n binary arrays with each element equal to at least two neighbors
0
0, 1, 1, 9, 86, 2986, 205020, 33329847, 11843513563, 9371551715962, 16360949033733903
OFFSET
1,4
COMMENTS
Diagonal of A180760
CROSSREFS
Sequence in context: A015581 A152261 A028339 * A266828 A100814 A055725
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 20 2010
STATUS
approved