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Characteristic (algebra)
In a field or a ring, the smallest positive integer, if any, such that the sum of n ones equals 0; zero otherwise
In mathematics, the characteristic of a ring R {\displaystyle R} , often denoted char ( R ) {\displaystyle \operatorname {char} (R)} , is defined to be the smallest positive number of copies of the ring's multiplicative identity (1) that will sum to the additive identity (0). If no such number exists, the ring is said to have characteristic zero.
From Wikipedia
In mathematics, the characteristic of a ring R {\displaystyle R} , often denoted char ( R ) {\displaystyle \operatorname {char} (R)} , is defined to be the smallest positive number of copies of the ring's multiplicative identity (1) that will sum to the additive identity (0). If no such number exists, the ring is said to have characteristic zero. That is, char ( R ) {\displaystyle \operatorname {char} (R)} is the smallest positive number n {\displaystyle n} such that 1 + ⋯ + 1 ⏟ n summands = 0 {\displaystyle \underbrace {1+\cdots +1} _{n{\text{ summands}}}=0} if such a number n {\displaystyle n} exists, and 0 {\displaystyle 0} otherwise.
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