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Old 2019-02-07, 00:48   #5
GP2
 
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Sep 2003

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From OEIS A028491, Paul Bourdelais has discovered a new base-3 repunit (probable) prime:

(3^2215303 − 1) /2 is a PRP


The Lifchitz PRP Top page shows two other discoveries in January for bases −6 and −7:

(6^1313371 + 1) /7
(7^1178033 + 1) /8

Last fiddled with by GP2 on 2019-02-07 at 00:58
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