Generates up to 18 decimal digit primes, or whatever is the number of digits of precision for a long double in the C compiler used to compile this utility.
A range may be specified on the command line, otherwise the starting number and the number of primes to output is prompted for. The range is "start" to "stop" inclusive, and "stop" must be greater than or equal to "start".
If "-t" or "twin" is specified on the command line, only twin primes will be displayed. Twin primes are two primes that differ in value by 2. Each twin pair is displayed together on the same line separated by a space character.
If "-p" or "pal" is specified on the command line, only palindromic primes are displayed. Palindromes are symmetrical, they read exactly the same forward and backward. The palindrome number base may be specified, the default is base 10. The base can be any integer greater than 1.