A107482 Number of prime factors of the smallest n-perfect number.

1, 2, 5, 10, 17, 31, 71, 137

Offset

1,2

Comments

Multiperfect numbers

Links

Table of n, a(n) for n=1..8.

Achim Flammenkamp, The Multiply Perfect Numbers Page.

Formula

a(n) = A001222(A007539(n))

Example

a(4)=10 because the smallest 4-perfect number factorization is 2^5*3^3*5*7 which has 10 prime factors.

Crossrefs

Cf. A107481

Sequence in context: A360749 A146268 A038358 * A227363 A372683 A342172

Adjacent sequences: A107479 A107480 A107481 * A107483 A107484 A107485

Keyword

hard,more,nonn

Author

Jose Brox (tautocrona(AT)terra.es), May 27 2005

Status

approved