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A317886
Numbers m such that 11^m + 6 is prime.
0
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
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
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