

A079139


Numbers n such that (Product of first n twin prime pair averages [A014574] ) + 1 is prime.


1




OFFSET

1,2


COMMENTS

a(3) and a(4) certified prime with Primo.


LINKS

Table of n, a(n) for n=1..6.


EXAMPLE

a(2)=5 because the product of the first five terms of A014574 + 1, 4*6*12*18*30+1 = 155521, is prime.


PROG

(PARI) { atp(N)= local(t, c); t=1; c=0; forprime(p=2, N, if(isprime(p+2), t*=p+1; c++; if(isprime(t+1), print1(c" ")))) }


CROSSREFS

Cf. A014574.
Sequence in context: A003185 A201876 A027801 * A269911 A249638 A188349
Adjacent sequences: A079136 A079137 A079138 * A079140 A079141 A079142


KEYWORD

more,nonn


AUTHOR

Jason Earls, Dec 26 2002


STATUS

approved



