A131558 Primes which are the sum of the first 10^k primes for some k.

2, 24133, 870530414842019, 11138479445180240497, 1948856725874605823462196012533593

Offset

1,1

Comments

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

Links

Table of n, a(n) for n=1..5.

Example

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.

Prog

(PARI)
sm=0;  ct=0;  p=1;  bb=1;
{ while ( 1,
    p = nextprime(p+1);  sm += p;  ct++;
    if ( (ct==bb), if ( isprime(sm), print1(sm, ", ")); bb*=10; );
); }

Crossrefs

Cf. A099824.

Sequence in context: A261362 A132942 A237521 * A133857 A349519 A232869

Adjacent sequences: A131555 A131556 A131557 * A131559 A131560 A131561

Keyword

nonn,more

Author

Cino Hilliard, Aug 27 2007

Extensions

a(5) from David Baugh, Sep 27 2016

Status

approved