Gmp.mpz bin(int k)
Return the binomial coefficient n over k , where n is the value of this mpz object. Negative values of n are supported using the identity
n
(-n)->bin(k) == (-1)->pow(k) * (n+k-1)->bin(k)
(See Knuth volume 1, section 1.2.6 part G.)
The k value can't be arbitrarily large. An error is thrown if it's too large.
This function is currently (Pike 7.8) not available with old releases of the gmp libraries.