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A093795 Numbers n such that 9^n+8^(n-1) is prime. 20
2, 7, 8, 31, 610, 1292, 4015, 5990, 8887, 9626, 57952, 62116, 84698 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(14) > 10^5. - Robert Price, Mar 05 2016

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

8 is a member since 98+87 = 45143873 which is a prime number.

MATHEMATICA

Do[ If[ PrimeQ[9^n + 8^(n - 1)], Print[n]], {n, 4000}]

PROG

(PARI) is(n)=isprime(9^n+8^(n-1)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A082103, A093717, A093793, A093765, A096185, A093794, A093795, A096186.

Sequence in context: A236291 A190175 A081700 * A001493 A000637 A250715

Adjacent sequences:  A093792 A093793 A093794 * A093796 A093797 A093798

KEYWORD

nonn,more

AUTHOR

Herman H. Rosenfeld (herm3(AT)pacbell.net), May 18 2004

EXTENSIONS

More terms from Robert G. Wilson v, Jun 18 2004

a(7)-a(13) from Robert Price, Mar 05 2016

STATUS

approved

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Last modified April 13 16:36 EDT 2021. Contains 342936 sequences. (Running on oeis4.)