An enumerator for the odd primes (i.e. all but 2)

OddPrimeEnumerator.cs

public class OddPrimeEnumerator : IEnumerator<int>
{
  private readonly IEnumerator<int> _candidates = 
    new NumberEnumerator(3, 2);
  private readonly IPriorityQueue<NumberEnumerator> _pq = 
    new IntervalHeap<NumberEnumerator>();

  public int Current
  {
    get { return _candidates.Current; }
  }

  public bool MoveNext()
  {
    while (true)
    {
      _candidates.MoveNext();
      int n = _candidates.Current;
      bool crossedOut = false;
      while (!crossedOut)
      {
        if (_pq.IsEmpty || n < _pq.FindMin().Current)
        {
          // There are no pending prime-multiples.
          // This means n is a prime!
          _pq.Add(new NumberEnumerator(n * n, n));
          return true;
        }
        crossedOut = n == _pq.FindMin().Current;
        do
        {
          var temp = _pq.DeleteMin();
          temp.MoveNext();
          _pq.Add(temp);
        } while ((n > _pq.FindMin().Current) ||
                 (crossedOut && n == _pq.FindMin().Current));
      }
    }
  }

  object IEnumerator.Current
  {
    get { return Current; }
  }

  public void Dispose() { }

  public void Reset()
  {
    throw new NotSupportedException();
  }
}