This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A005848 M2304 #41 Aug 09 2022 05:51:52 %S A005848 1,3,4,5,7,8,9,11,12,13,15,16,17,19,20,21,24,25,27,28,32,33,35,36,40, %T A005848 44,45,48,60,84 %N A005848 Cyclotomic fields with class number 1 (or with unique factorization). %C A005848 Note that if n == 2 (mod 4) Q(zeta_n) is the same field as Q(zeta_{n/2}), so this sequence omits numbers that are 2 mod 4. - Yuval Dekel, Jun 07 2003 %C A005848 Also note that 3 corresponds to Z[omega] (the Eisenstein integers) and 4 corresponds to Z[i] (the Gaussian integers). %C A005848 Alaca & Williams cite Masley & Montgomery, saying the earlier authors "prove that there are precisely 29 distinct cyclotomic fields" with class number 1 (mentioning the n = 2 mod 4 caveat), and then give this sequence without the initial 1. - _Alonso del Arte_, Mar 10 2017 %D A005848 Şaban Alaca & Kenneth S. Williams, Introductory Algebraic Number Theory. Cambridge: Cambridge University Press (2004): 343. %D A005848 F. Le Lionnais, Les Nombres Remarquables. Paris: Hermann, p. 85, 1983. %D A005848 J. Myron Masley, Where are the number fields with small class number?, pp. 221-242 of Number Theory Carbondale 1979, Lect. Notes Math. 751 (1982). %D A005848 Paulo Ribenboim, The Book of Prime Number Records. Springer-Verlag, NY, 2nd ed., 1989, p. 259. %D A005848 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A005848 Alf van der Poorten, Notes on Fermat's Last Theorem, Wiley, 1996, p. 14. %D A005848 L. C. Washington, Introduction to Cyclotomic Fields, Springer, p. 353. %H A005848 Michael Baake and Uwe Grimm, <a href="https://arxiv.org/abs/math/0203025">A note on shelling</a>, arXiv:math/0203025 [math.MG], 2002-2003. %H A005848 E. Bugarin, M. de las Peñas, and D. Frettlöh, <a href="http://arxiv.org/abs/0905.4048">Perfect colourings of cyclotomic integers</a>, arXiv:0905.4048 [math.GR], 2009-2012. %H A005848 Hendrik W. Lenstra and A. J. van der Poorten, <a href="https://doi.org/10.1007/BF03024378">Euclidean number fields 1</a>, Math. Intelligencer 2 (1979): pp. 6-15. %H A005848 J. Myron Masley and Hugh L. Montgomery, <a href="http://dx.doi.org/10.1515/crll.1976.286-287.248">Cyclotomic fields with unique factorization</a>, Journal für die reine und angewandte Mathematik 286/287 (1976), 248-256. %Y A005848 Cf. A061653. %K A005848 fini,nonn,full,nice %O A005848 1,2 %A A005848 _N. J. A. Sloane_