

A253380


Numbers n such that 17^n+4 is prime.


0




OFFSET

1,2


COMMENTS

No further terms up to 10000.


LINKS

Table of n, a(n) for n=1..5.


EXAMPLE

For n = 0: 17^0+4 = 5, which is prime, so 0 is a term of the sequence.
For n = 2: 17^2+4 = 293, which is prime, so 2 is a term of the sequence.


MATHEMATICA

Select[Range@10^5, PrimeQ[17^# + 4] &] (* Michael De Vlieger, Jan 03 2015 *)


PROG

(PARI) for(n=0, 1e5, if(ispseudoprime(17^n+4), print1(n, ", ")))


CROSSREFS

Corresponding sequences for k^n+4: A058958 (k=3), A124621 (k=5), A096305(k=7), A217384 (k=9), A137236 (k=13), A247166 (k=15), A243397 (k=19).
Sequence in context: A064535 A240643 A262971 * A128123 A227884 A186769
Adjacent sequences: A253377 A253378 A253379 * A253381 A253382 A253383


KEYWORD

nonn,more


AUTHOR

Felix FrÃ¶hlich, Dec 31 2014


STATUS

approved



