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MathGroup Archive 2005

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Re: Re:Numbers and their reversals

  • To: mathgroup at smc.vnet.net
  • Subject: [mg53756] Re: [mg53718] Re:Numbers and their reversals
  • From: DrBob <drbob at bigfoot.com>
  • Date: Wed, 26 Jan 2005 04:36:59 -0500 (EST)
  • References: <200501251003.FAA14366@smc.vnet.net>
  • Reply-to: drbob at bigfoot.com
  • Sender: owner-wri-mathgroup at wolfram.com

If we restrict ourselves to {2-digit, 3-digit, 4-digit} examples like yours (one of each size), there are a lot of examples with trivial GCD's, not counting simple palindromes.

Here are the first and last in a list of 131,759 such triples:

{11, 102, 1202}
{89, 991, 9987}

The divisors are 91 and 11 in those two cases.

and ten randomly chosen:

{{89, 474, 5554}, {72, 709, 6817}, {15, 488, 7861},
   {34, 287, 7611}, {48, 455, 6695}, {23, 463, 4377},
   {13, 794, 7764}, {23, 342, 7743}, {23, 661, 7952},
   {57, 376, 2891}}

with corresponding divisors

{{11}, {91}, {11}, {11}, {11}, {11}, {11}, {11}, {11}, {11}}

The frequency counts for divisors in the list is:

{{130182, 11}, {1577, 91}}

My notebook on this is at

http://www.eclecticdreams.net/DrBob/Notebooks/omari.nb

Bobby

On Tue, 25 Jan 2005 05:03:11 -0500 (EST), F. omari <towtoo2002 at yahoo.com> wrote:

>
> the reason of my previous question to mathgroup was that someone said that he has three weird numbers : 23 , 114 , 6236
> he said that when we arrange these numbers in pairs side by side with the smaller number first , and after that we reverse the pair we will get:
> 23114=7*13*254
> 41132=7*13*452
> 236236=7*13*2596
> 632632=7*13*6952
> 1146236=7*13*12596
> 6326411=7*13*69521
> he said that there are no other three numbers like these in all the world.
> it happened that pairings of these numbers are a subgroup from many numbers such as: 22, 113, 7227
> Thanks DrBob and Bob Hanlon and all for the in depth analysis and investigations
>
>
>



-- 
DrBob at bigfoot.com
www.eclecticdreams.net


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