%I #9 Sep 27 2016 05:31:02

%S 2,24133,870530414842019,11138479445180240497,

%T 1948856725874605823462196012533593

%N Primes which are the sum of the first 10^k primes for some k.

%C Also numbers n such that A099824(n) is prime.

%e The sum of the first 10^1 primes is 129 which is not prime and not in the sequence. The sum of the first 10^9 primes is 11138479445180240497 which is prime and in the sequence.

%o (PARI)

%o sm=0; ct=0; p=1; bb=1;

%o { while ( 1,

%o p = nextprime(p+1); sm += p; ct++;

%o if ( (ct==bb), if ( isprime(sm),print1(sm,", ")); bb*=10; );

%o ); }

%Y Cf. A099824.

%K nonn,more

%O 1,1

%A _Cino Hilliard_, Aug 27 2007

%E a(5) from _David Baugh_, Sep 27 2016