OFFSET
1,1
COMMENTS
Many terms in the sequence are squares: 6^2,10^2,12^2,18^2,20^2,24^2,28^2,30^2,36^2,40^2,44^2,48^2,50^2...
Abundant numbers that are coprime to their abundance (intersection of A005101 and A014567) are all terms. Abundant numbers that are not coprime to their abundance are 4-abundant (i.e., terms of A023198, e.g., 64468800, 121726800, 168480000, ...). - Waldemar Puszkarz and Amiram Eldar, Aug 15 2024
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[12000], Numerator[Total[1/Divisors@ #]] > 2 # &] (* Michael De Vlieger, May 04 2016 *)
PROG
(PARI) isok(n) = numerator(sigma(n)/n) > 2*n; \\ Michel Marcus, May 04 2016
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 07 2002
STATUS
approved