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

%I #13 Aug 12 2023 23:00:45

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

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

%C 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.

%Y Cf. A102687, A163859.

%Y Column k=4 of A247026.

%K more,nonn

%O 0,3

%A _Carlos Alves_, Aug 05 2009

%E a(0) from _Alois P. Heinz_, Sep 09 2014

%E a(8)-a(10) from _Bert Dobbelaere_, Jan 24 2019