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NextPrime, NextProbPrime --
find the next prime number
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NextPrime(N: INT): INT
NextProbPrime(N: INT): INT |
The first function computes the smallest prime number greater than
N.
If
N is too large then an error is signalled. The upper
limit depends on the computer you are using; it is probably
2^31
or
2^63.
The second function computes the smallest probable prime number greater than
N.
To be absolutely certain the number produced is prime,
you must call
IsPrime
on it, but this may be very costly.
The functions give errors if handed negative arguments.
NextProbPrime
uses
IsProbPrime
which cannot be interrupted, so be wary of
inputs larger than about
2^100000 (which already takes a few minutes).
/**/ NextPrime(1000);
1009
/**/ NextProbPrime(10^50);
100000000000000000000000000000000000000000000000151
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