A320573 - OEIS

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

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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 A206476

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