OFFSET
1,4
COMMENTS
a(n) is the number of prime divisors of the sum of prime divisors of n, counting multiplicity in both cases.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
f:= proc(n) local t; numtheory:-bigomega(add(t[1]*t[2], t=ifactors(n)[2])) end proc:
map(f, [$1..100]);
MATHEMATICA
Array[PrimeOmega[Plus@@Times@@@FactorInteger@#]&, 100] (* Giorgos Kalogeropoulos, Mar 31 2021 *)
PROG
(Python)
from sympy import factorint
def A342956(n): return sum(factorint(sum(p*e for p, e in factorint(n).items())).values()) if n > 1 else 0 # Chai Wah Wu, Mar 31 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Mar 30 2021
STATUS
approved