public void Test01() { // if n < 3,317,044,064,679,887,385,961,981, it is enough to test a = 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, and 41. @ wiki for (int c = 0; c < 10000; c++) { string s = string.Format("331704406467988738596{0:D4}", c); Console.WriteLine(s + " ==> " + PrimeUtils.IsPrime_M(Common.ToBigInteger(s))); } }