OFFSET
1,2
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..300
EXAMPLE
The divisors of 18 are {1,2,3,6,9,18}, so tau(18)=6 and sigma(18)=1+2+3+6+9+18=39, 18 is a term as 18*13=6*39=tau(18)*sigma(18).
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jun 03 2002
STATUS
approved