OFFSET
1,3
COMMENTS
The first n-fold perfect numbers are A007539(n) = 1, 6, 120, 30240, 14182439040, ..., for n = 1, 2, 3, 4, 5, ...
The first n-fold perfect numbers divided by 120 is A227766.
The first n-fold perfect numbers divided by 30240 is A227767.
The first n-fold perfect numbers divided by 14182439040 is A227768.
For additional comments, references, links, and cross-refs, see A007539.
LINKS
T. D. Noe, Table of n, a(n) for n = 1..8
E. W. Weisstein's MathWorld, Multiperfect Number
Wikipedia, Multiply perfect number
FORMULA
a(n) = A007539(n)/6 if 2 <= n <= 8.
EXAMPLE
The first 3-fold perfect number is A007539(3) = 120, so a(3) = 120/6 = 20.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Sondow, Jul 29 2013
STATUS
approved