cover of book Primes of the Form x2 + ny2:
Fermat, Class Field Theory, and Complex Multiplication

by David A. Cox
Amherst College
with contributions by Roger Lipsett

American Mathematical Society

Original Edition, 1989
Paperback Edition, 1997
Second Edition, 2013
Third Edition with Solutions, 2022

The Third Edition

The third edition of Primes of the Form x2 + ny2 was published in 2022 by the American Mathematical Society. The main features of the third edition are:

Typographical Errors in the Third Edtion

The known typographical errors are:

The Second Edition

The second edition of Primes of the Form x2 + ny2 was published in 2013 by John Wiley & Sons. The main features of the second edition are:

The other changes in the text are minor, mostly to enhance clarity, improve formatting, and simplify some of the proofs.

Typographical Errors in the Second Edition

The list of known typographical errors as of June 19, 2022 in the second edition is available in pdf .

Typographical Errors in the First Edition

Lists of typographical errors are available for the two printings of the hardback first edition. To find out which printing you have, check the bottom line on the copyright page; the last digit displayed is the printing number.

These lists contain errata discovered as of January 28, 2009. Any typos discovered after this date appear in the errata list for the softcover edition.

For the softcover first edition, many (but not all) of the typographical errors in the hardcover edition were corrected. The remaining errors are available in pdf or postscript .

All of these typos were corrected in the second edition of the book, which appeared in 2013.

Additional Exercises

For a nice set of exercises that supplement Chapter One of the book, click here. I am grateful to Jeffrey Stopple for preparing these exercises.

Ordering Information for the Third Edition

Click here for the AMS catalog page for the third edition of Primes of the Form x2 + ny2. This page includes a brief description of the book and information on how to order a copy.

Contacting the Author

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