OFFSET
1,2
COMMENTS
The corresponding quotients are 1, 3, 3, 5, 7, 7, 7, 7, 11, 13, 13, 13, 13, ...
a(14) > 7.5*10^10, if it exists. - Amiram Eldar, Jun 04 2021
FORMULA
{n: A064608(n) == 0 (mod n)}.
EXAMPLE
For n = 37, the sum A064608(37) = 1+2+2+2+2+4+2+...+4+4+4+2 = 111 = 3*37, so 37 is in the sequence.
MATHEMATICA
s[1] = 1; s[n_] := s[n] = s[n - 1] + 2^PrimeNu[n]; Select[Range[30000], Divisible[s[#], #] &] (* Amiram Eldar, Jun 04 2021 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Labos Elemer, Sep 24 2001
EXTENSIONS
a(10)-a(13) from Donovan Johnson, Jul 20 2012
STATUS
approved