A317886 Numbers m such that 11^m + 6 is prime.

0, 1, 2, 25, 26, 70, 130, 784, 818, 895, 7843, 41294, 114458, 160663, 281143

Offset

1,3

Comments

a(12) > 35000, if it exists. - Giovanni Resta, Aug 10 2018

For m = 3*k, (11^m + 6)/7 is an integer, so there are no multiples of 3 in this sequence.

After a(2), there are no terms congruent to 1 mod 16, because 11^(16*k+1) + 6 is divisible by 17. - Bruno Berselli, Sep 20 2018

Links

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

Example

11^2 + 6 = 127 is prime, hence 2 is a term.

Mathematica

Select[Range[0, 5000], PrimeQ[11^# + 6] &]

Prog

(PARI) for(n=0, 5000, if(ispseudoprime(11^n+6), print1(n, ", ")))

Crossrefs

Cf. A109076.

Sequence in context: A153811 A101962 A092045 * A054283 A041723 A067443

Adjacent sequences: A317883 A317884 A317885 * A317887 A317888 A317889

Keyword

nonn,more

Author

Jinyuan Wang, Aug 09 2018

Extensions

a(11) from Giovanni Resta, Aug 10 2018

a(12) from Lelio R Paula, Oct 2012

a(13)-a(14) from Paul Bourdelais, Feb 26 2021

a(15) from Paul Bourdelais, Mar 03 2021

Status

approved