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A227174 Numbers n such that (140^n + 139^n)/279 is prime. 1
23, 41, 43, 151, 2927, 6133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are prime.

a(7) > 10^4.

a(7) > 43400. - Lucas A. Brown, Nov 26 2020

LINKS

Table of n, a(n) for n=1..6.

PROG

(PARI) is(n)=ispseudoprime((140^n+139^n)/279) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A000978, A057469, A128066, A128335, A128336, A187805, A181141, A187819, A217095.

Sequence in context: A209985 A244323 A337871 * A050657 A050668 A199219

Adjacent sequences:  A227171 A227172 A227173 * A227175 A227176 A227177

KEYWORD

hard,nonn,more,changed

AUTHOR

Jean-Louis Charton, Jul 03 2013

STATUS

approved

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Last modified November 30 15:27 EST 2020. Contains 338807 sequences. (Running on oeis4.)