Delta omega, or , is a small number. It is smaller than all the positive reals but larger than zero and many other small numbers. It is defined as the fixed point of the delta numbers, as being equal to but not zero. It is thus larger than any number defined as a real power of zero, while still being smaller than every positive real number.
It is larger than δn for all odd n and smaller than all δn for even n. However, ω is not either odd or even, and thus ill-defined.