[seqfan] Re: x^(y + 1) - y^x

[Olivier Gerard]

Dear Youri,

In a certain sense the next one is {{3,16},129136067}

Please, learn to program with a mathematical system, such as Sage or Pari.
They are free and you will be able to test your hypothesis yourself.


Olivier

Here is a list for x and y below 50

{{2,1},3}
{{3,2},19}
{{2,3},7}
{{3,4},179}
{{7,6},543607}
{{3,16},129136067}
{{11,18},61159026180004467059}
{{3,22},94143168179}
{{5,22},11920928949924493}
{{7,24},1341068619659378429383}
{{3,40},36472996377170722403}
{{43,42},11038273990127811480919358457913344930118047775125063309170238812320819}
{{5,46},710542735760100185871124061615149}
{{9,46},706965049015104706497203195836692724380688313}
{{5,48},17763568394002504646778106434649157}







On Mon, Aug 18, 2014 at 8:44 PM, юрий герасимов <2stepan at rambler.ru> wrote:

>
> Dear SeqFans,
> primes of the form x^(y + 1) - y^x for positive x and y :
>
> 7 (x = 2, y = 3),
> 19 (x = 3, y = 2),
> 179 (x = 3, y = 4),
> 543607 (x = 7, y = 6), ....
>
> What in the next one?
> JSG
>
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