OFFSET
1,2
COMMENTS
Multiperfect numbers
LINKS
Achim Flammenkamp, The Multiply Perfect Numbers Page.
EXAMPLE
a(4)=10 because the smallest 4-perfect number factorization is 2^5*3^3*5*7 which has 10 prime factors.
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Jose Brox (tautocrona(AT)terra.es), May 27 2005
STATUS
approved