A217130 Numbers n such that 7^n + 6 is prime.

0, 1, 3, 16, 36, 244, 315, 2577, 9500, 17596, 25551, 32193, 32835, 36504, 75136

Offset

1,3

Comments

a(16) > 10^5. - Robert Price, Jan 24 2014

Links

Table of n, a(n) for n=1..15.

Mathematica

Select[Range[0, 5000], PrimeQ[7^# + 6] &]

Prog

(PARI) for(n=1, 5000, if(isprime(7^n+6), print1(n", ")))
(Magma) /* The code produces the sequence up to 315: */ [n: n in [0..2000] | IsPrime(7^n+6)];

Crossrefs

Cf. A236371, A217131, A191469, A090669, A096305, A217130, A217132, A152213.

Sequence in context: A359559 A076153 A031302 * A173390 A173891 A066875

Adjacent sequences: A217127 A217128 A217129 * A217131 A217132 A217133

Keyword

nonn

Author

Vincenzo Librandi, Oct 01 2012

Extensions

a(9)-a(15) from Robert Price, Jan 24 2014

Status

approved