A220905 - OEIS

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A220905

Triangle read by rows: rook numbers of certain "probleme des rencontres" boards of the second kind of size n X k (0 <= k <= n).

1, 1, 0, 1, 2, 0, 1, 6, 6, 2, 1, 24, 132, 176, 24, 1, 60, 960, 4580, 5040, 552, 1, 120, 4260, 52960, 213000, 206592, 21280, 1, 210, 14070, 368830, 3762360, 13109712, 11404960, 1073160

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

0,5

COMMENTS

Rows 0 through 2 were not given in the reference and should be checked. (There is a Maple program in the Appendix).

What are the row sums?

LINKS

Table of n, a(n) for n=0..35.

F. Alayont and N. Krzywonos, Rook Polynomials in Three and Higher Dimensions, 2012.

EXAMPLE

Triangle begins:

1, 0