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Function: void mpz_primorial_ui (mpz_t rop , unsigned long int n ) ¶ Set rop to the primorial of n , i.e. the product of all positive
prime numbers <= n . Function: void mpz_bin_ui (mpz_t rop , const mpz_t n , unsigned long int k ) ¶ Function: void mpz_bin_uiui (mpz_t rop , unsigned long int n , unsigned long int k ) ¶ Compute the binomial coefficient n over k and store the result in rop .