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A099775 Primes of the form pq - 6, where p and q are consecutive primes. 1
29, 71, 137, 317, 431, 661, 1511, 3121, 3593, 4751, 6551, 8627, 9791, 11657, 16631, 19037, 36857, 41983, 51977, 55681, 57593, 72893, 82913, 95471, 116933, 123191, 159191, 194471, 198901, 205187, 210671, 233267, 256021, 272477, 324893, 364801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes of the form prime(k)*prime(k+1) - 6 for some k >= 1. - Jon E. Schoenfield, Jan 17 2015

LINKS

Table of n, a(n) for n=1..36.

EXAMPLE

11*13 - 6 = 137 is prime.

MATHEMATICA

f[n_]:=Prime[n]*Prime[n+1]-6; lst={}; Do[If[PrimeQ[f[n]], AppendTo[lst, f[n]]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 10 2010 *)

PROG

(PARI) p=2; forprime(q=3, 610, if(isprime(u=p*q-6), print1(u, ", ")); p=q)

(PARI) forprime(p=2, 1000, q=nextprime(p+1); r=p*q-6; if(isprime(r), print1(r, ", "))) \\ (Shepherd)

CROSSREFS

Cf. A092761.

Sequence in context: A141891 A144313 A218561 * A139893 A063312 A210499

Adjacent sequences:  A099772 A099773 A099774 * A099776 A099777 A099778

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Nov 12 2004

EXTENSIONS

Edited and extended by Klaus Brockhaus and Rick L. Shepherd, Nov 13 2004

STATUS

approved

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Last modified October 21 06:55 EDT 2019. Contains 328292 sequences. (Running on oeis4.)