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A079139 Numbers n such that (Product of first n twin prime pair averages [A014574] ) + 1 is prime. 1
1, 5, 45, 218, 506, 538 (list; graph; refs; listen; history; text; internal format)
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: A302726 A201876 A027801 * A269911 A249638 A188349

Adjacent sequences:  A079136 A079137 A079138 * A079140 A079141 A079142

KEYWORD

more,nonn

AUTHOR

Jason Earls, Dec 26 2002

STATUS

approved

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Last modified November 17 19:15 EST 2018. Contains 317276 sequences. (Running on oeis4.)