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Mrs.Z

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Can you prove that 10 is a solitary number?


A solitary number is one which does not have any friends. Solitary numbers include all primes, prime powers, and numbers for which (n,sigma(n))=1, where (a,b) is the greatest common divisor of a and b and sigma(n) is the divisor function.


The first few numbers satisfying (n,sigma(n))=1 are 1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 19, 21, ... (Sloane's A014567). Numbers such as 18, 45, 48, 52, 136, 148, 160, 162, 176, 192, 196, 208, 232, 244, 261, 272, 292, 296, 297, 304, 320, 352, and 369 can also be easily proved to be solitary.


But can you prove if 10 is solitary?

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can you tell me why people register in multiple names, then set questions only to answer themselves (via their other posing names)even though all the questions and answers are typed in exactly the same styles.(including puntuation, closed brackets ect)do others smell a rat or even a mouse here. Boring though it is,no?


some times posting from their I-Phones & laZily lEaving little keystroke errors beHind as cLues ?

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jimmy two times Wrote:

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> *pokes tongue out at LadyMuck and does a runner*


*blows raspberry at JTT*


iaineasy Wrote:

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>but without further evidence of the OP's problem solving prowess it may be a short lived one.


I am inclined to agree. Let's hope she's just procrastinating.

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jimmy two times Wrote:

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> Yeah go on...name and shame the bounder.


_________________________________________________


JTT


Well, I would love to name them but I have been "asked nicely" not to pick on them, so.....


(I'm a big bully like Gordon Brown you see, it's all the years at boarding school that's made me ....well, so mean at times)


BUT you could guess and I could say "Hotter" or "Colder" maybe ?


That way the ol' fella wouldn't feel picked on ( by me ) or victimised




W**F

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