A143881 Number of ways of placing kings with no more than 3 mutual attacks on an n X n chessboard.

1, 2, 15, 207, 6084, 292607, 23511001, 3132847224, 693856861039, 259806377729539

Offset

0,2

Links

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

Crossrefs

Cf. A143870, A143875, A143886.

Cf. A143882, A143883, A143884, A143885.

Sequence in context: A020565 A282521 A099718 * A298692 A361617 A132493

Adjacent sequences: A143878 A143879 A143880 * A143882 A143883 A143884

Keyword

nonn,more,hard

Author

R. H. Hardin, Sep 04 2008

Status

approved