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A319096
Number of nonequivalent ways to place n^2 nonattacking kings on a 2n X 2n chessboard under all symmetry operations of the square.
2
1, 14, 459, 35312, 4072108, 638653285, 128441726634, 31872148398195, 9490641145219266, 3321018871480028710
OFFSET
1,2
COMMENTS
A maximum of n^2 nonattacking kings may be placed on a 2n X 2n chessboard.
FORMULA
a(n) = A236679(2n+1, n^2).
EXAMPLE
For n = 2 there are a(2) = 14 distinct solutions from 79 that will not be repeated at all possible turns and reflections.
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3. 4.
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7. 8.
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9. 10.
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11. 12.
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13. 14.
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CROSSREFS
Cf. A018807 (rotations and reflections considered distinct).
Cf. A137432 (on cylindrical chessboard).
Sequence in context: A201546 A305115 A282245 * A297548 A215787 A005790
KEYWORD
nonn,more
AUTHOR
Anton Nikonov, Dec 21 2018
EXTENSIONS
a(4)-a(10) from Andrew Howroyd, Dec 21 2018
STATUS
approved