A163949 The number of functions in a finite set that are not obtainable by a composition power of any other function. Similar to A163947, but it excludes self compositions.

0, 3, 15, 138, 1720, 27180, 522984

Offset

1,2

Comments

It is similar to A163947, but the difference is expressed by the nontrivial sequence: 0, 3, 9, 54, 320, 1590, 6552... excluding solutions by powers of the function itself.

Links

Table of n, a(n) for n=1..7.

Formula

a(n) = n^n - A163950(n).

Crossrefs

Cf. A163947, A163950.

Sequence in context: A113379 A267018 A262911 * A005816 A179470 A270524

Adjacent sequences: A163946 A163947 A163948 * A163950 A163951 A163952

Keyword

more,nonn

Author

Carlos Alves, Aug 06 2009

Status

approved