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A374936
Maximum number of squares covered (i.e., attacked) by 6 independent (i.e., nonattacking) queens on an n X n chessboard.
4
36, 49, 64, 81, 100, 121, 142, 165, 186, 209, 231, 255, 277
OFFSET
6,1
EXAMPLE
Example for 12 X 12: There are 2 cells marked 'o' or uncovered thus a(12) = 12 * 12 - 2 = 142.
x x x x x x x x x x x Q
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x Q x x x x x x x x
x x x x x Q x x x x x x
x x x x x x x Q x x x x
x x x x Q x x x x x x x
x x x x x x Q x x x x x
o x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x o x x x
From Christian Sievers, Sep 08 2024: (Start)
Example for 14 X 14 with 186 attacked squares (unattacked ones marked with "+"):
. . Q . . . . . . . . . . .
. . . . . . . . . Q . . . .
. . . . . . . . . . . . . +
. + . . . . . . . . . . . .
. . . Q . . . . . . . . . .
. . . . . . . . . . . . . .
. . . . . . . . . . . . . .
. . . . . . . . . . . . Q .
. + . . . . . . . . . . . .
. . . . . . . . . . . . . +
. . . . . . Q . . . . . . .
. + . . + . . . . . . + . .
. . . . . + . . . . + . . +
Q . . . . . . . . . . . . .
(End)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
John King, Aug 08 2024
EXTENSIONS
a(14) corrected and a(15) confirmed by Christian Sievers, Sep 08 2024
a(16)-a(18) added using data from Mia Muessig by Andrew Howroyd, Oct 05 2024
STATUS
approved