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A093713 Numbers n such that 6^n-5^(n-1) is prime. 15
1, 2, 3, 4, 5, 12, 16, 18, 21, 42, 66, 69, 123, 132, 165, 204, 397, 401, 486, 657, 1005, 1050, 1882, 2545, 2813, 3168, 4092, 4151, 4469, 5358, 9168, 11554, 11866, 80946 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(35) > 10^5. - Robert Price, May 04 2016

LINKS

Table of n, a(n) for n=1..34.

MATHEMATICA

Do[ If[ PrimeQ[6^n - 5^(n - 1)], Print[n]], {n, 2000}]

PROG

(PARI) is(n)=isprime(6^n-5^(n-1)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A093765.

Sequence in context: A132027 A306077 A103651 * A057472 A117577 A109849

Adjacent sequences:  A093710 A093711 A093712 * A093714 A093715 A093716

KEYWORD

nonn,more

AUTHOR

Herman H. Rosenfeld (herm3(AT)pacbell.net) and Robert G. Wilson v, Jun 17 2004

EXTENSIONS

a(24)-a(34) from Robert Price, May 04 2016

STATUS

approved

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Last modified May 25 01:26 EDT 2019. Contains 323534 sequences. (Running on oeis4.)