Avoid infinite loop for finding large prime values #2126
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If the `val` passed to `findPrimeGreaterThan` is greater than the largest value (not the sentinel) in the `NC_primes`, then the routine will fall into an infinite loop. Modified to call an external routine that brute forces the finding of a prime larger than the value in this case. The brute force routine uses the primes in `NC_primes` table in the prime test, so this will fail if given a `value > 180503 * 180503`. The `isPrime` function could be rewritten to avoid this, but assuming this won't happen for the forseeable future. If it does happen, `isPrime` will return that any value larger than this is prime...
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If the
valpassed tofindPrimeGreaterThanis greater than the largest value (not the sentinel) in theNC_primes, then the routine will fall into an infinite loop. Modified to call an external routine that brute forces the finding of a prime larger than the value in this case.The brute force routine uses the primes in
NC_primestable in the prime test, so this will fail if given avalue > 180503 * 180503. TheisPrimefunction could be rewritten to avoid this, but assuming this won't happen for the forseeable future. If it does happen,isPrimewill return that any value larger than this is prime...