Hi, A couple of problems encountered with mp_math_v02 from the Vault: - Should line 315 of mp_math/mp_int/detail/integral_ops.hpp read "lhs.multiply_by_digit(static_cast<typename MpInt::digit_type>(rhs));" instead of "lhs.mul_digit(static_cast<typename MpInt::digit_type>(rhs));" ? "mul_digit" seems not to be defined. - prime_tab_impl::values gets defined multiple times, because the assignment is in the header. You could use a singleton class and e.g. Eratosthenes' sieve to fill the array with primes. That should stay header-only. Rgds, Mikko