

A181499


Triangle read by rows: number of solutions of n queens problem for given n and given number of conflicts


4



0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 10, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 28, 0, 0, 8, 4, 0, 0, 0, 0, 0, 64, 0, 28, 0, 0, 0, 0, 0, 0, 232, 0, 96, 24, 0, 0, 0, 0, 0, 0, 240, 0, 372, 112, 0, 0, 0, 0, 0, 88, 0, 0, 328, 1252, 872, 140, 0, 0, 0, 0, 0, 0, 0, 0, 3016, 5140, 4696, 1316, 32, 0, 0, 0, 0, 0
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,13


LINKS



FORMULA

Row sum = A000170 (number of n queens placements)
Column 0 has same values as A007705 (torus n queens solutions)
Column 1 is always zero.


EXAMPLE

For n=4, there are only the two solutions 2413 and 3142. Both have two conflicts So the terms for n=4 are 0 (0 solutions for n=4 having 0 conflicts), 0, 2 (the two cited above), 0 and 0. These are members 10 to 15 of the sequence.


CROSSREFS



KEYWORD



AUTHOR



STATUS

approved



