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 A234695 Primes p with prime(p) - p + 1 also prime. 38
 2, 3, 5, 7, 13, 17, 23, 31, 41, 43, 61, 71, 83, 89, 103, 109, 139, 151, 173, 181, 199, 211, 223, 241, 271, 277, 281, 293, 307, 311, 317, 337, 349, 353, 367, 463, 499, 541, 563, 571, 601, 661, 673, 709, 719, 743, 751, 757, 811, 823, 827, 883, 907, 911, 953 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS By the conjecture in A234694, this sequence should have infinitely many terms. LINKS Zhi-Wei Sun, Table of n, a(n) for n = 1..10000 Z.-W. Sun, Problems on combinatorial properties of primes, arXiv:1402.6641, 2014 FORMULA a(n) = prime(A234852(n)). - M. F. Hasler, Dec 31 2013 EXAMPLE a(1) = 2 since prime(2) - 1 = 2 is prime. a(2) = 3 since prime(3) - 2 = 3 is prime. a(3) = 5 since prime(5) - 4 = 7 is prime. a(4) = 7 since prime(7) - 6 = 11 is prime. MATHEMATICA n=0; Do[If[PrimeQ[Prime[Prime[k]]-Prime[k]+1], n=n+1; Print[n, " ", Prime[k]]], {k, 1, 1000}] PROG (PARI) forprime(p=1, 999, isprime(prime(p)-p+1)&&print1(p", ")) \\ - M. F. Hasler, Dec 31 2013 CROSSREFS Cf. A000040, A014692, A234694. Sequence in context: A089438 A155777 A262839 * A067905 A042993 A308711 Adjacent sequences:  A234692 A234693 A234694 * A234696 A234697 A234698 KEYWORD nonn AUTHOR Zhi-Wei Sun, Dec 29 2013 STATUS approved

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Last modified August 13 05:41 EDT 2020. Contains 336442 sequences. (Running on oeis4.)