A class number formula expresses the class number of a number field, or of an order in a number field, in terms of other invariants. For a quadratic field, the class number is denoted , where is its discriminant, and explicit formulas involve Dirichlet L-series.

See also

Class Number, Ring

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Cite this as:

Weisstein, Eric W. "Class Number Formula." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/ClassNumberFormula.html

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