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A189859
Number of ways to place n nonattacking composite pieces rook + rider[3,5] on an n X n chessboard.
2
1, 2, 6, 24, 120, 464, 2274, 13236, 91760, 740562, 5305548, 43237840, 395858894, 4087066620, 46633569480, 509698057110
OFFSET
1,2
COMMENTS
a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+3k)-p(i)|<>5k AND |p(j+5k)-p(j)|<>3k for all i>=1, j>=1, k>=1, i+3k<=n, j+5k<=n
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Vaclav Kotesovec, Apr 29 2011
STATUS
approved