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Old 2011-07-18, 05:47   #1
JohnFullspeed
 
May 2011
France

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Default Numberr of prime.

I'm looking to the algorithm to compute the number of PTIMES(not divisors)

sample
how many ptimes less 10^10?

Thanks
John
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Old 2011-07-18, 06:35   #2
cheesehead
 
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http://mathworld.wolfram.com/PrimeCountingFunction.html
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Old 2011-07-18, 08:37   #3
JohnFullspeed
 
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Red face To easy

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Old 2011-07-18, 09:37   #4
ldesnogu
 
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Tomas Oliveira e Silva has a nice article describing his implementation of Meissel-Lehmer-Lagarias-Miller-Oldyzko-Deléglise-Rivat combinatorial method.
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Old 2011-07-18, 11:12   #5
science_man_88
 
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Quote:
Originally Posted by JohnFullspeed View Post
john so is your iq test result.
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Old 2011-07-18, 15:12   #6
JohnFullspeed
 
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Default iq

Just after you have doubled
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Old 2011-07-18, 15:39   #7
JohnFullspeed
 
May 2011
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Default PrimeList

Merci de ce lien .
J'ai mis au point une méthode et je suis fier de voir quelle ressemble beaucoup à celle
de Legendre!
C'est pareil pour la factorisation ;je suis tout aussi fier d'avoir vu que c'était la même que Fermat
Moi je sais que je n'ai pas copié: c'est une belle revanche sur la maladie

C'est pareil pour la division:personne ne me croit mais je suis sur d'aller
plus vite que les méthodes connues: aucune multiplication (de chiifres et de nombre) Un jour peut être un matheux se penchera dessus.
En attendant une petite question pour s'occuper

SI vous divisez un nombre n par deux, vous obtenez deux ensembles de n/2 éléments..
Existe-t-il une même règle mais pour les nombres premiers

il y a 25 NP< 100 mais pas 50 <200

Pas facile: même de notre Belle Province
(je n'ai pas la solution mais j'en ai vu un qui dormait)


John
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Old 2011-07-18, 21:14   #8
firejuggler
 
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Over the rainbow

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*translator hat*

Thanks for the link.
I made a methode myself, and i'm pround that it look like Legendre's a lot.
It is the same thing for factorisation :I'm also pround to find that it is the same as Fermat's. Iknow I didn't copy them : it's a nice comeback from disease.

It's the same for the divisions : nobody believe me but i'm sure to go faster than the know method : no multiplication ( digit or number s). Maybe someday a math wizard will take a look at it.
While waiting on that, another question

If you divine a number N by 2, you obtain 2 set of 2/n element..
Does such a rule exist for prime numbers?
there is 25 prime <100, but not 50 under 200

Not easy; even from the belle province ( Quebec, french talking part of Canada)
(I do not have the solution, but i've seen one around ) (sorry can't translate that one accuratly. It make no sense as such in french , so I translated as I think he did mean)
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Old 2011-07-19, 06:20   #9
firejuggler
 
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replace the unclever 'disease' by illness...

Et pis, john, non, je ne maitrise pas le français , je parle bien l'anglais ;p. Je suis de la 'moche' province...je suis français.

(and, John i do not master french , I handle english ;p. I'm from the 'ugly' province... i'm french)
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Old 2011-07-19, 12:23   #10
JohnFullspeed
 
May 2011
France

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Cela devient difficile: des Francais qui ne perlent pas Francais ,mais qui le traduise benet qui habite au Canada Anglais
On dirait du Corneiie
John
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