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. All numbers displayed by this utility are guaranteed to be decimal (base 10) prime numbers. A prime number is an integer that cannot be factored.
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 the -c option is specified, the number of lines of primes displayed is limited to the decimal count that follows this option.
If the -t or "twin" option 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 the -p or "pal" option is specified on the command line, only palindromic primes are displayed. Palindromes are symmetrical, they read exactly the same forward and backward. The palindromic number base may be specified, the default is base 10. The base can be any integer greater than 1. Primes are always displayed in decimal (base 10).
Short help is displayed when given the -h option.