private IEnumerable<long> GetHammingPrimes(IEnumerable<long> hammingNumbers) { var primeUtils = new Prime((long)Math.Ceiling(Math.Sqrt(Limit)) + 100); foreach (var hammingNumber in hammingNumbers) { if (primeUtils.IsPrimeCompute(hammingNumber + 1) && hammingNumber < Limit && hammingNumber > 5) { yield return hammingNumber + 1; } } }