prime numbers

[aidasa2001]

I need a program which can say the number (input)is prime and then write other prime numbers with that digits.
eg.for 13 print the number is prime and print 113( another prime num with that digits)
tanx a lot

[JosAH]

I need a program which can say the number (input)is prime and then write other prime numbers with that digits.
eg.for 13 print the number is prime and print 113( another prime num with that digits)
tanx a lot

Ok, start at the beginning: what makes a number a prime number?

kind regards,

Jos

[r035198x]

I need a program which can say the number (input)is prime and then write other prime numbers with that digits.
eg.for 13 print the number is prime and print 113( another prime num with that digits)
tanx a lot

You are going to have to write it yourself. We are here only to give you hints and point you in the right direction not help you cheat on your assignment.

Design your program first. You need a method, isPrime, which takes a number and returns true iff that number is prime ....

[blazedaces]

I need a program which can say the number (input)is prime and then write other prime numbers with that digits.
eg.for 13 print the number is prime and print 113( another prime num with that digits)
tanx a lot

Shouldn't it be all numbers less then that one with those digits? I mean, theoretically there are infinitely many prime numbers, so when are you going to stop checking for them? The largest possible double?

-blazed

[JosAH]

Shouldn't it be all numbers less then that one with those digits? I mean, theoretically there are infinitely many prime numbers, so when are you going to stop checking for them? The largest possible double?

-blazed

That's an interesting question: given the digits of a prime number, is the set
of all possible prime numbers given a rearrangement of those digits where the
digits can be used multiple times, finite or not? I don't know the answer to that.
I suspect infinity ...

kind regards,

Jos

[r035198x]

That's an interesting question: given the digits of a prime number, is the set
of all possible prime numbers given a rearrangement of those digits where the
digits can be used multiple times, finite or not? I don't know the answer to that.
I suspect infinity ...

kind regards,

Jos

I'd say it's an infinite set.

The fact that primes are infinite is disproved by assuming the maximum prime P and finding a prime greater than P. If that set were finite, then there would be a prime P that is the largest prime in that set (pigeon hole) and it would be possible to find an infinite amount of primes greater than that prime. My bet is that in those infinite primes, the'd be at least one that contains the digits in some order.

[JosAH]

I'd say it's an infinite set.

The fact that primes are infinite is disproved by assuming the maximum prime P and finding a prime greater than P. If that set were finite, then there would be a prime P that is the largest prime in that set (pigeon hole) and it would be possible to find an infinite amount of primes greater than that prime. My bet is that in those infinite primes, the'd be at least one that contains the digits in some order.

That's my suspicion too bit it still isn't a proof; are there infinitely many primes
having just the single digit 2, 3, 5 or 7 in it? For the single digit primes there
aren't and that's a (lame) counter example. But how about more than one
unique digit primes? (like 17, 23 or whatever)

kind regards,

Jos

[eutynem]

how are you doing......Name is Jane

what is the easiest code that would give the following output....

Please enter two integers: 9 13

9: 3

10: 2 5

11: Prime

12: 2 3 4 6

13: Prime

There are 2 prime numbers.

The average value of the prime numbers is 12.00

Please enter two integers.

<email :removed>

[r035198x]

how are you doing......Name is Jane

what is the easiest code that would give the following output....

Please enter two integers: 9 13

9: 3

10: 2 5

11: Prime

12: 2 3 4 6

13: Prime

There are 2 prime numbers.

The average value of the prime numbers is 12.00

Please enter two integers.

<email :removed>

Please start your own thread for this and when you do so follow the guidelines.

[JosAH]

how are you doing......Name is Jane

what is the easiest code that would give the following output....

Please enter two integers: 9 13

9: 3

10: 2 5

11: Prime

12: 2 3 4 6

13: Prime

There are 2 prime numbers.

The average value of the prime numbers is 12.00

Please enter two integers.

<email :removed>

I already answered your question here.

kind regards,

Jos

[prometheuzz]

That's an interesting question: given the digits of a prime number, is the set
of all possible prime numbers given a rearrangement of those digits where the
digits can be used multiple times, finite or not? I don't know the answer to that.
I suspect infinity ...

kind regards,

Jos

From the number 2, no other prime can be constructed. Which of course goes for all single digit primes... Which I now read, is a lame counter example!
; )

[JosAH]

From the number 2, no other prime can be constructed. Which of course goes for all single digit primes... Which I now read, is a lame counter example!
; )

Yep, totally lame; but what about two or more distinct digits that make up a
prime number? I haven't the faintest idea and I don't have enough spare time
on my hands to dig into it either. It'll always be a mystery as far as I am
concerned.

kind regards,

Jos ;-)