public static int truncatableprimes(int n) { int count = 0; int sum = 0; PrimeFunctions.GeneratePrimesToList(1000000); PrimeFunctions.ConvertToHash(); int i = 4; while (count < n) { bool isprime = true; List <int> trunc = CombinatoricFunctions.truncations(PrimeFunctions.PrimeList[i]); foreach (int truncation in trunc) { if (!PrimeFunctions.PrimeListHash.Contains(truncation)) { isprime = false; break; } } if (isprime) { count++; sum += PrimeFunctions.PrimeList[i]; } i++; } return(sum); }