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Old 2016-03-10, 19:41   #1
PawnProver44
 
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Post Sequence of primes formation

I am trying to prove that there are only finitely many of the form k*b^n+c for relatively prime integers k, b, and c. I came across my first example, that there are no primes of the form 34*10^n+3 for n > 0. Is this true. If not, please show me that there are other primes of this form.
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Old 2016-03-10, 20:16   #2
paulunderwood
 
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Code:
? for(n=0,200,if(ispseudoprime(34*10^n+3),print(n)))
0
86
154
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Old 2016-03-11, 00:55   #3
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So my record failed I take it?
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Old 2016-03-11, 00:59   #4
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Quote:
Originally Posted by PawnProver44 View Post
So my record failed I take it?
any time k+c is prime n=0 works as a counter to there not being one.
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Old 2016-03-11, 04:43   #5
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Quote:
Originally Posted by PawnProver44 View Post
So my record failed I take it?
What are you talking about?

Also, do you know what "relatively prime" means? If so, why did you provide an example where the numbers are not relatively prime?

Your statement of what you're trying to prove isn't precise enough. Do you mean you are looking for a combination of k,b,c such that there are only finitely many primes of your form? Or are you trying to say that for ANY relatively prime k-b-c there are only finitely many primes?

You should look up what a Riesel number or Sierpinski number are. Or, check the conjectures R us subforum. You'll find examples of k values with *no* primes.
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Old 2016-03-11, 05:56   #6
LaurV
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What are you trying to convince him to do??!??!?!
He can't be bothered to read srsieve help (30 lines of text), and he has not a freaking idea what a file name is. You want to teach him integrals and programming?

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Old 2016-03-11, 06:02   #7
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Quote:
Originally Posted by VBCurtis View Post
What are you talking about?

Also, do you know what "relatively prime" means? If so, why did you provide an example where the numbers are not relatively prime?

Your statement of what you're trying to prove isn't precise enough. Do you mean you are looking for a combination of k,b,c such that there are only finitely many primes of your form? Or are you trying to say that for ANY relatively prime k-b-c there are only finitely many primes?

You should look up what a Riesel number or Sierpinski number are. Or, check the conjectures R us subforum. You'll find examples of k values with *no* primes.
There are no primes of the form 34*10^n+3 except 37. I was seeing if this would be proved true or false.
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Old 2016-03-11, 06:10   #8
LaurV
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Quote:
Originally Posted by PawnProver44 View Post
There are no primes of the form 34*10^n+3 except 37. I was seeing if this would be proved true or false.
paulunderwood just gave you another two counterexamples.
3400..(another 80 zeroes)..0003 is prime.
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Old 2016-03-11, 06:19   #9
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Awww... come on.... I had tested this form for months and now I just broke the record.
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Old 2016-03-11, 07:38   #10
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Hey PawnProver44, I know what you are up to just by reading all your posts. I see you want to find large PRPs or even just primes. You had the right idea of using programs like PFGW or srsieve, but don't constantly point out typical errors.... please learn to fix some yourself. Also, before writing a thread on something you are not sure about, look on the search bar first to see if someone else encountered the same problem. Too many threads or replies on the same topic isn't good. If you have a critical problem that no one has encountered before and you cannot do anything about it, then consider starting a thread. The problems you encounter are not really "problems" because it seems like you did not read what everyone else was saying important. LaurV gave you complete instruction on how to run srsieve, so you should be set there. Another possible reason you may be encountering problems running programs is due to your personal computer issues. Hope this helps you understand what you are having trouble with.
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Old 2016-03-11, 07:41   #11
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Also, Please do not start anymore new threads. With the posts you started, and you could just read carefully what everyone else was saying, you would be able to find several PRPs or primes by now.
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