The nonnegative integers 0, 1, 2, ....
Z^*
See also
Counting Number, Natural Number, Nonnegative, Whole Number Z, Z--, Z-+Explore with Wolfram|Alpha
References
Barnes-Svarney, P. and Svarney, T. E. The Handy Math Answer Book, 2nd ed. Visible Ink Press, 2012.Cite this as:
Weisstein, Eric W. "Z^*." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Z-Star.html