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A128072
Numbers k such that (3^k + 14^k)/17 is prime.
10
3, 7, 71, 251, 1429, 2131, 2689, 36683, 60763
OFFSET
1,1
COMMENTS
All terms are primes.
a(10) > 10^5. - Robert Price, Apr 20 2013
MATHEMATICA
k=14; Do[ p=Prime[n]; f=(3^p+k^p)/(k+3); If[ PrimeQ[f], Print[p]], {n, 1, 100} ]
PROG
(PARI) is(n)=isprime((3^n+14^n)/17) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Cf. A007658 (numbers k such that (3^k + 1)/4 is prime).
Cf. A057469 (numbers k such that (3^k + 2^k)/5 is prime).
Cf. A122853 (numbers k such that (3^k + 5^k)/8 is prime).
Cf. A059801 (numbers k such that 4^k - 3^k is prime).
Cf. A121877 (numbers k such that (5^k - 3^k)/2 is prime).
Sequence in context: A127179 A359748 A113841 * A094008 A209477 A209336
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Feb 14 2007
EXTENSIONS
3 more terms from Ryan Propper, Jan 28 2008
a(8)-a(9) from Robert Price, Apr 20 2013
STATUS
approved