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A348130
Number of ways to place n nonattacking queens on a 2n X 2n board.
1
1, 4, 44, 1024, 34568, 1535440, 84871680, 5613017128, 432539436508, 38053315307904, 3763518275715424
OFFSET
0,2
FORMULA
a(n) = A348129(2n,n).
EXAMPLE
a(1) = 4:
+-----+ +-----+ +-----+ +-----+
| Q . | | . . | | . Q | | . . |
| . . | | Q . | | . . | | . Q |
+-----+ +-----+ +-----+ +-----+ .
CROSSREFS
Cf. A348129.
Sequence in context: A053333 A374279 A301942 * A255928 A137783 A136552
KEYWORD
nonn,hard,more
AUTHOR
Alois P. Heinz, Oct 01 2021
EXTENSIONS
a(9)-a(10) from Martin Ehrenstein, Oct 06 2021
STATUS
approved