LMFDB definition
Class numbers
The class number of a number field is the order of the ideal class group of .
David Farmer, Holly Swisher. CC BY-SA 4.0. Snapshot 2026-09-22; formatting adapted for this site.
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conjecturesconjecturesLMFDB definition
The class number of a number field is the order of the ideal class group of .
David Farmer, Holly Swisher. CC BY-SA 4.0. Snapshot 2026-09-22; formatting adapted for this site.