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• A quick question if I may. If a prime number does not have the same digit occuring within it more than once, what is that number called (and yes I know there
Message 1 of 12 , Nov 12, 2009
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A quick question if I may. If a prime number does not have the same digit occuring within it more than once, what is that number called (and yes I know there are a finite number of them all being < 10**9). Example, 97 is such a number but 101 is not.

James

[Non-text portions of this message have been removed]
• ... They are simply called primes with distinct digits in http://www.research.att.com/~njas/sequences/A029743 which says: This sequence has 283086 terms, the
Message 1 of 12 , Nov 12, 2009
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James J Youlton Jr wrote:
> If a prime number does not have the same digit occuring
> within it more than once, what is that number called (and yes
> I know there are a finite number of them all being < 10**9).

They are simply called primes with distinct digits in
http://www.research.att.com/~njas/sequences/A029743
which says:
"This sequence has 283086 terms, the last being 987654103"

As you apparently know, 3 divides any permutation of 0123456789.

--
Jens Kruse Andersen
• Oh my, what a disappointment. I thought for sure they would have a name. Perhaps we can name them? Three possibilities among many occur to me: Unidigital
Message 1 of 12 , Nov 12, 2009
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Oh my, what a disappointment. I thought for sure they would have a name. Perhaps we can name them?

Three possibilities among many occur to me: "Unidigital Primes", "Monodigital Primes", or "Solodigital Primes".

I'm making a puzzle contest and I'm looking for a name to call them if one exists or can be named.

James

----- Original Message -----
From: Jens Kruse Andersen
Sent: Thursday, November 12, 2009 6:43 PM

James J Youlton Jr wrote:
> If a prime number does not have the same digit occuring
> within it more than once, what is that number called (and yes
> I know there are a finite number of them all being < 10**9).

They are simply called primes with distinct digits in
http://www.research.att.com/~njas/sequences/A029743
which says:
"This sequence has 283086 terms, the last being 987654103"

As you apparently know, 3 divides any permutation of 0123456789.

--
Jens Kruse Andersen

[Non-text portions of this message have been removed]
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