OFFSET
1,2
EXAMPLE
The sum of first 3 primes 2+3+5 = 10 has exactly 2 distinct prime divisors, 3 is the smallest prime with this property, so that a(2) = 3.
PROG
(PARI) a(n) = my(k=1); while (omega(sum(i=1, k, prime(i))) != n, k++); k; \\ Michel Marcus, Jul 15 2021
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Metin Sariyar, Jul 14 2021
EXTENSIONS
a(12)-a(15) from Martin Ehrenstein, Jul 17 2021
STATUS
approved