A109076 -id:A109076 - cp's OEIS frontend

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

Jinyuan Wang, Aug 09 2018

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

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

Cf. A109076.

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

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

a(11) from Giovanni Resta, Aug 10 2018
a(12) from Lelio R Paula, Feb 02 2021
a(13)-a(14) from Paul Bourdelais, Feb 26 2021
a(15) from Paul Bourdelais, Mar 03 2021

A359695 Numbers k such that 29^k - 2 is prime.

Original entry on oeis.org

2, 4, 8, 14, 42, 420, 1344

Offset: 1

Arsen Vardanyan, Mar 07 2023

a(8) > 10^4, if it exists. - Amiram Eldar, Mar 10 2023
All terms in this sequence are even. - Yifan Xie, Mar 12 2023
a(8) > 5*10^4, if it exists. - Michael S. Branicky, Sep 14 2024

			4 is a term because 29^4 - 2 = 707279 is a prime number.

Cf. A087886 (29^k + 2 is prime).

Cf. A128460, A128459, A128457, A109076, A090669, A105772, A109080, (and similar others).

Select[Range[1400], PrimeQ[29^# - 2] &] (* Amiram Eldar, Mar 10 2023 *)

PARI
```
is(k) = isprime(29^k - 2);
```

cp's OEIS Frontend

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

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