Kronecker symbol

In number theory, the Kronecker symbol, written as ${\displaystyle \left({\frac {a}{n}}\right)}$ or ${\displaystyle (a|n)}$, is a generalization of the Jacobi symbol to all integers ${\displaystyle n}$. It was introduced by Leopold Kronecker (1885, page 770).

Let ${\displaystyle n}$ be a non-zero integer, with prime factorization

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