OFFSET
1,2
LINKS
Bruno Berselli, Table of n, a(n) for n = 1..1000
PROG
(Magma) Ad:=func<h | h*(&+[Factorisation(h)[i][2]/Factorisation(h)[i][1]: i in [1..#Factorisation(h)]])>; [0] cat [Ad(n^3): n in [2..40]]; // Bruno Berselli, Oct 22 2013
(Python)
from sympy import factorint
def A068721(n): return 3*n**2*sum((n*e//p for p, e in factorint(n).items())) if n > 1 else 0 # Chai Wah Wu, Nov 03 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Feb 26 2002
STATUS
approved