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A163860

Number of different 4th-power (quartic) mappings of a finite set of n elements into itself.

1, 1, 3, 12, 73, 580, 5721, 69244, 1000210, 16319601, 297453340

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OFFSET

0,3

COMMENTS

The same as A102687 for square composition, as A163859 for cubic compositions, here a(n) is the number of different mappings g that admit at least one mapping f as the 4th-order root (g=fofofof) in terms of the composition.

LINKS

Table of n, a(n) for n=0..10.

CROSSREFS

Cf. A102687, A163859.

Column k=4 of A247026.

Sequence in context: A245506 A275385 A247055 * A246382 A104028 A074510

Adjacent sequences: A163857 A163858 A163859 * A163861 A163862 A163863

KEYWORD

more,nonn

AUTHOR

Carlos Alves, Aug 05 2009

EXTENSIONS

a(0) from Alois P. Heinz, Sep 09 2014

a(8)-a(10) from Bert Dobbelaere, Jan 24 2019

STATUS

approved