A143886 Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard.

1, 2, 15, 267, 9450, 577785, 58537749, 9751519234, 2673230750387, 1220300742842014

Offset

0,2

Links

Table of n, a(n) for n=0..9.

Crossrefs

Cf. A143870, A143875, A143881.

Cf. A143887, A143888, A143889, A143890, A143891, A143892, A143893.

Sequence in context: A195737 A192567 A354980 * A174482 A076111 A371673

Adjacent sequences: A143883 A143884 A143885 * A143887 A143888 A143889

Keyword

nonn,more,hard

Author

R. H. Hardin, Sep 04 2008

Status

approved