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391 is special too

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Dale Shoults

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May 21, 2013, 7:40:54 PM5/21/13
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I came across a website that listed something special about each positive integer up to 391, and about many greater than 391, bur not for 391. So here's something that is potentially interesting or special about 391:

The 3rd, 9th & 1st digits of 391^((9/3 + 9/1 + 3/1)^2) are 3, 9 & 1, respectively.

William Elliot

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May 21, 2013, 10:00:35 PM5/21/13
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On Tue, 21 May 2013, Dale Shoults wrote:

> I came across a website that listed something special about each
> positive integer up to 391, and about many greater than 391, bur not for
> 391. So here's something that is potentially interesting or special
> about 391:

Theorem. All integers are interesting.

Proof. Assume there's an uninteresting integer.
Then there's a least uninteresting integer which, being
the least uninteresting integer, is interesting. QED.

Roland Franzius

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May 21, 2013, 11:24:02 PM5/21/13
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Am 22.05.2013 01:40, schrieb Dale Shoults:
> I came across a website that listed something special about each positive integer up to 391, and about many greater than 391, bur not for 391. So here's something that is potentially interesting or special about 391:
>
> The 3rd, 9th & 1st digits of 391^((9/3 + 9/1 + 3/1)^2) are 3, 9 & 1, respectively.
>


So we have to discard 391 as the conjectured smallest number, having no
interesting properties at all.

--

Roland Franzius

Peter Percival

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May 22, 2013, 7:07:05 AM5/22/13
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William Elliot wrote:
> On Tue, 21 May 2013, Dale Shoults wrote:
>
>> I came across a website that listed something special about each
>> positive integer up to 391, and about many greater than 391, bur not for
>> 391. So here's something that is potentially interesting or special
>> about 391:
>
> Theorem. All integers are interesting.
>
> Proof. Assume there's an uninteresting integer.
> Then there's a least uninteresting integer

I think you need to say positive integer.

> which, being
> the least uninteresting integer, is interesting. QED.
>
>> The 3rd, 9th & 1st digits of 391^((9/3 + 9/1 + 3/1)^2) are 3, 9 & 1,
>> respectively.
>
>


--
I think I am an Elephant,
Behind another Elephant
Behind /another/ Elephant who isn't really there....
A.A. Milne

William Elliot

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May 23, 2013, 1:09:08 AM5/23/13
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On Wed, 22 May 2013, Peter Percival wrote:
> William Elliot wrote:
> >
> > Theorem. All integers are interesting.
> >
> > Proof. Assume there's an uninteresting integer.
> > Then there's a least uninteresting integer
>
> I think you need to say positive integer.
>
Yup, any bounded below set of integers.

Actually the argument can be reused to show there's
no uninteresting negative number.

Pfs...@aol.com

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May 23, 2013, 11:04:25 AM5/23/13
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Math definition of "special" ????
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