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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
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
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 A356496
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, Oct 02 2014
EXTENSIONS
a(16)-a(20) from Robert Price, Jul 07 2015
STATUS
approved