[seqfan] Re: Primes in primes

[Ami Eldar]

The next term is > 10000.

On Sun, Oct 28, 2018 at 5:00 PM Tomasz Ordowski <tomaszordowski at gmail.com>
wrote:

> Dear SeqFans!
>
> Primes of the form 1+2^1+2^2+...+2^(p-1) are Mersenne primes 2^p-1 for p =
> 2,3,5,7,13,17,19,...
>
> Let's rise higher and define:
>
> Primes p such that q =
> 1+2^(2-1)+2^(3-1)+2^(5-1)+2^(7-1)+2^(11-1)+...+2^(p-1) is prime.
>
> Data: 2, 3, 5, 19, 2039, 2879, ... The last two primes I have from Robert
> Israel.
>
> The prime p = 19 gives the prime q = 332887 = 1010001010001010111.
>
> The positions of 1's (read from the end): 1, 2, 3, 5, 7, 11, 13, 17, 19.
>
> Cf. https://oeis.org/A080355
>
> Best regards.
>
> Thomas
>
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