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 A296818 Squarefree values of k for which the quadratic field Q[ sqrt(k) ] possesses a norm-Euclidean 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 norm-Euclidean number field is a norm-Euclidean ideal. In other words, this sequence is the union of {-15, -5, 10, 15, 85} and A048981. LINKS Kelly Emmrich and Clark Lyons, Norm-Euclidean 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. 121-131. EXAMPLE -5 is in the sequence because the ideal (2, 1+sqrt(-5)) is norm-Euclidean 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

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Last modified March 23 20:39 EDT 2023. Contains 361452 sequences. (Running on oeis4.)