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A269133 Number of ways to place m nonattacking queens on an m X n board, 1 <= m <= n (triangular array). 1
1, 2, 0, 3, 2, 0, 4, 6, 4, 2, 5, 12, 14, 12, 10, 6, 20, 36, 46, 40, 4, 7, 30, 76, 140, 164, 94, 40, 8, 42, 140, 344, 568, 550, 312, 92, 9, 56, 234, 732, 1614, 2292, 2038, 1066, 352, 10, 72, 364, 1400, 3916, 7552, 9632, 7828, 4040, 724, 11, 90, 536, 2468, 8492, 21362, 37248, 44148, 34774, 15116, 2680, 12, 110, 756, 4080, 16852, 52856, 120104, 195270, 222720, 160964, 68264, 14200 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..78.

Math StackExchange, State space for eight queen problem

Marko Riedel, Perl program to compute triangular array of nonattacking queens configurations

EXAMPLE

The triangular array begins:

n\m 1  2   3   4    5     6     7      8      9      10     11    12

1   1

2   2  0

3   3  2   0

4   4  6   4   2

5   5  12  14  12   10

6   6  20  36  46   40    4

7   7  30  76  140  164   94    40

8   8  42  140 344  568   550   312    92

9   9  56  234 732  1614  2292  2038   1066   352

10  10 72  364 1400 3916  7552  9632   7828   4040   724

11  11 90  536 2468 8492  21362 37248  44148  34774  15116  2680

12  12 110 756 4080 16852 52856 120104 195270 222720 160964 68264 14200

...

CROSSREFS

Cf. A000170 (m=n).

Cf. A000027 (m=1), A002378 (m=2), A061989 (m=3), A061990 (m=4), A061991 (m=5), A061992 (m=6), A061993 (m=7), A172449 (m=8).

Sequence in context: A141432 A115241 A154559 * A143324 A287416 A097418

Adjacent sequences:  A269130 A269131 A269132 * A269134 A269135 A269136

KEYWORD

nonn,tabl

AUTHOR

Marko Riedel, Feb 19 2016

STATUS

approved

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Last modified October 22 06:02 EDT 2018. Contains 316432 sequences. (Running on oeis4.)