A187819 - OEIS

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A187819

Numbers k such that (9^k + 8^k)/17 is prime.

15

3, 7, 13, 19, 307, 619, 2089, 7297, 75571, 76103, 98897

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OFFSET

1,1

COMMENTS

All terms are prime.

a(12) > 10^5.

LINKS

Table of n, a(n) for n=1..11.

MATHEMATICA

Select[ Prime[ Range[1, 100000] ], PrimeQ[ (9^# + 8^#)/17 ]& ]

PROG

(PARI) is(n)=isprime((9^n+8^n)/17) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A181141, A128339, A057175, A125956.

Sequence in context: A023230 A194581 A106080 * A310266 A330407 A014283

Adjacent sequences: A187816 A187817 A187818 * A187820 A187821 A187822

KEYWORD

nonn,hard,more

AUTHOR

Robert Price, Dec 26 2012

STATUS

approved