[seqfan] Re: Problem
Tomasz Ordowski
tomaszordowski at gmail.com
Sun Jul 19 11:14:20 CEST 2020
P.S. Note.
It is known that there exist such composites:
even m = k-1 and odd 2m+1 = 2k-1,
where k is a Riesel number;
https://oeis.org/A101036
sob., 18 lip 2020 o 21:01 Tomasz Ordowski <tomaszordowski at gmail.com>
napisał(a):
> Dear SeqFans!
>
> Let a(0) = p and a(n) = 2 a(n-1) + 1. Note that a(n) = (p+1) 2^n - 1.
> Are there primes p such that a(n) is composite for every n > 0 ?
>
> Best regards,
>
> Thomas Ordowski
> _______________________
> https://en.wikipedia.org/wiki/Riesel_number
>
>
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