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 A247962 Numbers n such that 51^n + 2 is prime. 2
 0, 1, 5, 6, 15, 24, 25, 66, 72, 309, 330, 594, 1000, 1142, 1882, 2482, 2725, 30106, 65176, 85334 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Numbers ending with 8 are not in the sequence. - Bruno Berselli, Oct 02 2014 a(21) > 2*10^5. - Robert Price, Jul 07 2015 LINKS Henri & Renaud Lifchitz, PRP Top Records, Search for 51^n+2. MAPLE A247962:=n->`if`(isprime(51^n+2), n, NULL): seq(A247962(n), n=0..500); # Wesley Ivan Hurt, Oct 02 2014 MATHEMATICA Select[Range[0, 2000], PrimeQ[51^# + 2] &] PROG (MAGMA) [n: n in [0..300]| IsPrime( 51^n + 2 )]; (PARI) is(n)=ispseudoprime(51^n+2) \\ Charles R Greathouse IV, Jun 06 2017 CROSSREFS Cf. similar sequences listed in A247957. Sequence in context: A329634 A227066 A115908 * A241307 A185876 A091020 Adjacent sequences:  A247959 A247960 A247961 * A247963 A247964 A247965 KEYWORD nonn,more AUTHOR Vincenzo Librandi, Oct 02 2014 EXTENSIONS a(16)-a(20) from Robert Price, Jul 07 2015 STATUS approved

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Last modified September 19 05:11 EDT 2020. Contains 337175 sequences. (Running on oeis4.)