1,2
Multiperfect numbers
Achim Flammenkamp, The Multiply Perfect Numbers Page.
a(n) = A001222(A007539(n))
a(4)=10 because the smallest 4-perfect number factorization is 2^5*3^3*5*7 which has 10 prime factors.
Cf. A107481
Sequence in context: A173520 A146268 A038358 * A018315 A146220 A054964
Adjacent sequences: A107479 A107480 A107481 * A107483 A107484 A107485
hard,more,nonn
Jose Brox (tautocrona(AT)terra.es), May 27 2005
