Re: Prime numbers

To compute whether a number is a prime number, my script:
1. Tests if even or multiple of five, if true then not prime,
2. Tests for factors, if true then not prime, by:
i. Halving, because factors are less than half, then for every possible factor:
i.a. Testing if that number is even or multiple of five, if true then not prime,
i.b. Testing if that number leaves no remainder when divisor of original number, if true then not prime,
Else the number is prime.

Does anyone know of a more efficient method?

Jerome K Maule McKean



On 03/04/2005 03:01, Mr. J. K M. McKean wrote: 
https://dreamfrequency.com/primes.html

Optimised code, giving large speed improvement.

Jerome K Maule McKean



On 27/03/2005 19:25, Mr. J. K M. McKean wrote:

Calculates all the prime numbers below a number.

https://dreamfrequency.com/primes.html

Jerome K Maule McKean 
.

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