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A352599
Number of ways of placing A352426(n) nonattacking white-square queens on an n X n board.
1
1, 2, 4, 6, 2, 6, 64, 112, 68, 80, 32, 36, 28, 1414, 576, 384, 40, 70396, 40896, 22468, 9808, 1152, 252, 2246138, 482272, 185932
OFFSET
1,2
COMMENTS
Equivalently the number of ways of placing the maximal number of nonattacking black-square queens on an inverted n X n chessboard, that is a board with the a1 square white, the a2 and b1 squares black, etc.
FORMULA
a(2n) = A352325(2n).
PROG
(Python) See A352426.
CROSSREFS
Cf. A352241 (maximal number for black-squares), A352325 (black-squares counts), A352426 (maximal number for white-squares), this sequence (white-squares counts).
Sequence in context: A133903 A278263 A236188 * A373902 A242593 A094752
KEYWORD
nonn,hard,more
AUTHOR
Martin Ehrenstein, Mar 22 2022
EXTENSIONS
a(21)-a(24) from Vaclav Kotesovec, Mar 23 2022
a(25)-a(26) from Vaclav Kotesovec, Apr 01 2022
STATUS
approved