OFFSET
0,5
LINKS
Max Alekseyev, Table of n, a(n) for n = 0..100
EXAMPLE
a(4)=312399=3^2*103*337 since sigma(3^2*103*337)=(13)*(2^3*13)*(2*13^2)=2^4*13^4 and 312399 is the smallest such number.
CROSSREFS
KEYWORD
nonn
AUTHOR
Walter Kehowski, Sep 06 2010
EXTENSIONS
Terms a(17) onward from Max Alekseyev, Mar 04 2014
STATUS
approved