

A131558


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


0




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 A232869 A153912
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



