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 A034849 a(n) = 1 + 2*A034784(n). 4
 7, 11, 17, 19, 23, 29, 31, 41, 43, 47, 53, 59, 67, 71, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 163, 167, 173, 179, 181, 191, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 281, 283, 293, 307, 311, 317, 331 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The terms are odd prime numbers. LINKS Michael De Vlieger, Table of n, a(n) for n = 1..10000 MATHEMATICA 1 + 2 Position[#, 2] &@ Table[k = 1; While[! PrimeQ[k n + 1], k++]; k, {n, 165}] // Flatten (* Michael De Vlieger, Jul 31 2017 *) PROG (PARI) lista(nn) = for (n=1, nn, if (isprime(p=2*n+1) && !isprime(n+1), print1(p, ", ")); ); \\ Michel Marcus, Aug 01 2017 CROSSREFS Cf. A034693, A034694, A034784. Sequence in context: A163996 A117743 A216495 * A269256 A106070 A038880 Adjacent sequences:  A034846 A034847 A034848 * A034850 A034851 A034852 KEYWORD nonn AUTHOR EXTENSIONS Edited by N. J. A. Sloane, Oct 27 2012 STATUS approved

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Last modified April 20 20:26 EDT 2021. Contains 343137 sequences. (Running on oeis4.)