code: function randProbPrime(k) {
    if (k>=600) return randProbPrimeRounds(k, 2); //numbers from HAC table 4.3
    if (k>=550) return randProbPrimeRounds(k, 4);
    if (k>=500) return randProbPrimeRounds(k, 5);
    if (k>=400) return randProbPrimeRounds(k, 6);
    if (k>=350) return randProbPrimeRounds(k, 7);
    if (k>=300) return randProbPrimeRounds(k, 9);
    if (k>=250) return randProbPrimeRounds(k, 12); //numbers from HAC table 4.4
    if (k>=200) return randProbPrimeRounds(k, 15);
    if (k>=150) return randProbPrimeRounds(k, 18);
    if (k>=100) return randProbPrimeRounds(k, 27);
                return randProbPrimeRounds(k, 40); //number from HAC remark 4.26 (only an estimate)
  }
docs: return a k-bit random probable prime with probability of error < 2^-80