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A143883
Number of ways of placing kings with no more than 3 mutual attacks on an n X n chessboard symmetric about main diagonal.
1
1, 2, 7, 29, 160, 1135, 10529, 125770, 1963039, 39868375, 1061669314, 37110747097, 1708827058427
OFFSET
0,2
CROSSREFS
Sequence in context: A030956 A329259 A185310 * A346427 A003437 A192410
KEYWORD
nonn,more,hard
AUTHOR
R. H. Hardin, Sep 04 2008
STATUS
approved