# [seqfan] Re: A168022

Alonso Del Arte alonso.delarte at gmail.com
Fri Nov 30 18:23:46 CET 2012

```Just a little note: the BackIssues.com link still works and it still shows
the cover of the Scientific American issue. It is oriented the same way as
MathWorld has it but different from YouTube.

Al

On Fri, Nov 30, 2012 at 5:57 AM, Paolo Lava <paoloplava at gmail.com> wrote:

> Juri,
>
>
>
> numbers n such that 4^(n + 1) - 3*2^n + 1 is prime
>
>
>
> 0, 1, 2, 3, 4, 5, 6, 9, 10, 14, 16, 19, 33, 35, 39, 62, 68, 69, 70, 96,
> 115, 122, 213, 265, 304, 364, 666, 864, 953, 1448,…
>
>
>
> Bye
>
>
>
> Paolo
>
>
> 2012/11/25 юрий герасимов <2stepan at rambler.ru>
>
> >
> > if
> > A168022(non-composite numbers in the eastern ray of the Ulam spiral as
> > oriented on the March iover of Scentific American) are 1, 2, 11, 53, 127,
> > 233, 541, 743, 977, 1871, 3511,..
> > then A_____? = (2^n)-th numbers in the eastem ray of the Ulam spiral as
> > oriented on the March iover of Scientific American = 2, 11, 53, 233, 977,
> > 4001, 16193, 65153, 261377, 1047041, 4191233, 16771073, 67096577,
> > 268410881, 1073692673, 4294868993, 171796725577, 68719083521,
> 274877120513,
> > 1099507957763, 4398043365377, 17592179752961, 70368731594753,
> > 281474951544833,...
> > or A         ? = (numbers n such that 4^(n + 1) - 3*2^n + 1 is prime) =
> >  0, 1, 2, 3, 4, 5, 6, 8, 9, 14, 16, a(11) = ?, a(12) = ?, a(13) = ?  Dear
> > Segfans, help calculat the number o this sequence by computer.
> > Regards, Juri-Stepan Gerasimov
> > ______________________________**_________________
> >
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>

--
Alonso del Arte
Author at SmashWords.com<https://www.smashwords.com/profile/view/AlonsoDelarte>
Musician at ReverbNation.com <http://www.reverbnation.com/alonsodelarte>

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