A320573 a(n) gives the number of configurations of non-attacking rooks on an n X n chessboard such that the number of distinct distances between the rooks is given by A320448(n).

1, 2, 6, 8, 8, 24, 48, 32, 32, 16, 48, 24, 144, 72

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Example

For n = 6 the a(6) = 24 solutions are the eight symmetries of
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Crossrefs

Cf. A319476, A320575, A320576, A320448, A320573, A320574.

Sequence in context: A136702 A328910 A064165 * A003610 A201776 A379389

Adjacent sequences: A320570 A320571 A320572 * A320574 A320575 A320576

Keyword

nonn,more

Author

Peter Kagey, Oct 15 2018

Extensions

a(11)-a(14) from Giovanni Resta, Oct 21 2018

Status

approved