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A144241
Number of n X n binary arrays, symmetric about the diagonal and under 90-degree rotation, with every 1 adjacent to at least one other 1 both bishopwise and rookwise but with no three 1s in a row bishopwise or rookwise.
0
1, 2, 1, 3, 2, 4, 4, 13, 10, 65, 30, 231, 168, 1370, 1317, 17525, 10846, 191939, 133498, 2802218, 2431795, 73051050, 54458173, 2202863847, 1575946900, 84041510893, 69906212126, 5035951361562, 4061748253676, 385626222267420
OFFSET
1,2
CROSSREFS
Sequence in context: A282971 A174618 A365006 * A094173 A214370 A227859
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 15 2008
STATUS
approved