A005778 Rook polynomials.

1, 9, 72, 320, 1185, 3892, 11776, 33480, 90745, 236808, 599112, 1477216, 3564001, 8439960, 19666688, 45183824, 102520881, 230046452, 511085960, 1125313056, 2457641857, 5327760940, 11471647872, 24547187800, 52225646057, 110524638672

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Earl Glen Whitehead, Jr., Four-discordant permutations, J. Austral. Math. Soc. Ser. A 28 (1979), no. 3, 369-377.

Crossrefs

A diagonal of A259985.

Extensions

More terms from Sean A. Irvine, Aug 27 2016