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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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).

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%I A320574 #10 Oct 22 2018 01:38:58
%S A320574 1,1,2,1,1,3,6,4,4,2,6,3,18,9
%N 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).
%C A320574 Conjecture: a(n) = A320573(n)/8 for all n > 3.
%H A320574 Giovanni Resta, <a href="/A320574/a320574.pdf">Illustration of a(3)-a(14)</a>
%e A320574 For n = 6 the a(6) = 3 configurations with A320448(6) = 11 distinct distances are:
%e A320574 +---+---+---+---+---+---+
%e A320574 | * |   |   |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   | * |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   | * |   |   |   |   |
%e A320574 +---+---+---+---+---+---+,
%e A320574 |   |   |   |   | * |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   |   |   | * |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   | * |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 +---+---+---+---+---+---+
%e A320574 | * |   |   |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   | * |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   |   |   | * |
%e A320574 +---+---+---+---+---+---+, and
%e A320574 |   |   |   | * |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   |   | * |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   | * |   |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 +---+---+---+---+---+---+
%e A320574 | * |   |   |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   | * |   |   |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   |   | * |   |
%e A320574 +---+---+---+---+---+---+.
%e A320574 |   |   |   | * |   |   |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   |   |   |   | * |
%e A320574 +---+---+---+---+---+---+
%e A320574 |   |   | * |   |   |   |
%e A320574 +---+---+---+---+---+---+
%Y A320574 Cf. A319476, A320575, A320576, A320448, A320573, A320574.
%K A320574 nonn,more
%O A320574 1,3
%A A320574 _Peter Kagey_, Oct 15 2018
%E A320574 a(10)-a(14) from _Giovanni Resta_, Oct 21 2018