OFFSET
0,1
COMMENTS
If n has repeated prime factors, then these are added as indicated by the exponents. For example, 18336 = 2^5 * 3 * 191, therefore we add 2 five times in our sum to obtain the next term of the sequence. - Alonso del Arte, Jul 12 2011
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
EXAMPLE
For n = 3, n is a prime number so the next term is 6.
For n = 6, n is not a prime factor, as n = 2*3, so the next term = 6+2+3 = 11.
MATHEMATICA
a[1] := 3; a[n_] := a[n] = a[n - 1] + Plus@@Times@@@FactorInteger@a[n - 1]; Table[a[n], {n, 40}] (* Alonso del Arte, Jul 12 2011 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Lawrence Hollom, Jul 12 2011
EXTENSIONS
More terms from Vincenzo Librandi and Alonso del Arte, Jul 12 2011
Offset corrected to 0 (so as to have a(n) = n times iterated A001414 acting on the initial value) by M. F. Hasler, Jul 18 2011
STATUS
approved