Set of Whole Numbers Z
The doublestruck capital letter Z, Z, denotes the ring of integers ..., -2, -1, 0, 1, 2, .... The symbol derives from the German word Zahl, meaning "number", and first appeared in Bourbaki's Algèbre (reprinted as Bourbaki 1998, p. 671). The ring of integers is sometimes also denoted using the double-struck capital I, I.
C | counting number | C^* | N | natural number | Q | R | ring of integers | whole number | Z^- | Z^+ | Z^*