

A296818


Squarefree values of k for which the quadratic field Q[ sqrt(k) ] possesses a normEuclidean ideal class.


2



15, 11, 7, 5, 3, 2, 1, 2, 3, 5, 6, 7, 10, 11, 13, 15, 17, 19, 21, 29, 33, 37, 41, 57, 73, 85
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OFFSET

1,1


COMMENTS

This generalizes A048981, because the unit ideal of a normEuclidean number field is a normEuclidean ideal. In other words, this sequence is the union of {15, 5, 10, 15, 85} and A048981.


LINKS

Table of n, a(n) for n=1..26.
Kelly Emmrich and Clark Lyons, NormEuclidean Ideals in Galois Cubic Fields, Slides, West Coast Number Theory, Dec 18 2017.
H. W. Lenstra, Jr., Euclidean ideal classes, Soc. Math. France Astérisque, 1979, pp. 121131.


EXAMPLE

5 is in the sequence because the ideal (2, 1+sqrt(5)) is normEuclidean in the number field Q[ sqrt(5) ].


CROSSREFS

Cf. A003174, A048981.
Sequence in context: A013461 A013430 A131082 * A097953 A200522 A273445
Adjacent sequences: A296815 A296816 A296817 * A296819 A296820 A296821


KEYWORD

fini,sign,full,nice


AUTHOR

Robert C. Lyons, Dec 22 2017


STATUS

approved



