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 A186104 Primes of the form 3*6^n - 1. 4
 2, 17, 107, 647, 23327, 139967, 30233087, 6530347007, 39182082047, 14215144014964850687, 240614901699187213221099227578367, 53193679461858262403856737876228196870083927814929645567 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For the exponents n see A186106. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..21 PROG (MAGMA) [3*6^n-1: n in [0..140] | IsPrime(3*6^n-1)]; // Bruno Berselli, Feb 12 2011 (PARI) v=[]; for(n=0, 1e3, if(ispseudoprime(k=3*6^n-1), v=concat(v, k))); v \\ Charles R Greathouse IV, Jul 26 2011 CROSSREFS Sequence in context: A105652 A204238 A198796 * A155845 A115354 A100274 Adjacent sequences:  A186101 A186102 A186103 * A186105 A186106 A186107 KEYWORD nonn AUTHOR Gilbert Mozzo, Feb 12 2011 EXTENSIONS Edited by N. J. A. Sloane, Feb 12 2011 STATUS approved

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Last modified December 8 03:17 EST 2021. Contains 349590 sequences. (Running on oeis4.)