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 A079140 Numbers n such that (Product of first n twin prime pair averages [A014574] ) - 1 is prime. 0
 1, 2, 7, 11, 16, 32, 402 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Some of the larger entries may only correspond to probable primes. LINKS EXAMPLE a(2)=2 because the product of the first two terms of A014574 - 1, 4*6-1 = 23, is prime. PROG (PARI) {atm(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: A190518 A190750 A049635 * A176897 A166005 A243009 Adjacent sequences:  A079137 A079138 A079139 * A079141 A079142 A079143 KEYWORD more,nonn AUTHOR Jason Earls (zevi_35711(AT)yahoo.com), Dec 26 2002 STATUS approved

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Last modified December 13 09:05 EST 2017. Contains 295957 sequences.