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A320574
a(n) gives the number of configurations of non-attacking rooks up to symmetry on an n X n chessboard such that the number of distinct distances between the rooks is given by A320448(n).
6
1, 1, 2, 1, 1, 3, 6, 4, 4, 2, 6, 3, 18, 9
OFFSET
1,3
COMMENTS
Conjecture: a(n) = A320573(n)/8 for all n > 3.
EXAMPLE
For n = 6 the a(6) = 3 configurations with A320448(6) = 11 distinct distances are:
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CROSSREFS
KEYWORD
nonn,more
AUTHOR
Peter Kagey, Oct 15 2018
EXTENSIONS
a(10)-a(14) from Giovanni Resta, Oct 21 2018
STATUS
approved