

A296818


Squarefree values of n for which the quadratic field Q[ sqrt(n) ] 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
(list;
graph;
refs;
listen;
history;
text;
internal format)



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 AstÃ©risque, 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



