A001328 Number of equivalence classes of n-valued Post functions of 2 variables under action of semi-direct product of symmetric groups S_2 and S(2,n). (Formerly M4309 N1804)

6, 438, 3962646, 10417184196975, 9954761196199929077325, 5057490251219818192322424165975972, 1930587876541100645614895805509354549563927698736, 746598793682620583344610283857629170831782164188262315836348333960

Offset

2,1

References

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

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

Links

Table of n, a(n) for n=2..9.

M. A. Harrison and R. G. High, On the cycle index of a product of permutation groups, J. Combin. Theory, 4 (1968), 277-299.

Crossrefs

Cf. A001324.

Sequence in context: A028665 A231316 A270066 * A174777 A265168 A187514

Adjacent sequences: A001325 A001326 A001327 * A001329 A001330 A001331

Keyword

nonn

Author

N. J. A. Sloane

Extensions

More terms from Sean A. Irvine, Oct 08 2015

Typo in a(3) corrected by Sean A. Irvine, Nov 03 2015

Status

approved