XION

#!/usr/bin/xion

function isprime n
    if n < 2 then return false
    repeat with x = 2 to the sqrt of n
        if n mod x == 0 then return false
    end repeat
    return true
end isprime

on primes cnt
    repeat with x = 0 to cnt
        if isprime(x) then
            put x
        end if
    end repeat
end primes

ask "List primes up to:" with "50"
if it is not empty and the result is not "Cancel" then primes it