This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A014600 Class numbers h(D) of imaginary quadratic fields with discriminant D=0,1 mod 4, D<0. 5
 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 3, 2, 1, 1, 3, 2, 2, 2, 4, 2, 1, 3, 5, 2, 2, 2, 4, 4, 3, 2, 4, 2, 1, 4, 7, 2, 2, 3, 5, 4, 3, 4, 6, 2, 2, 3, 8, 4, 2, 2, 5, 6, 3, 3, 8, 2, 2, 6, 10, 4, 2, 3, 5, 4, 5, 4, 6, 4, 3, 6, 10, 4, 2, 2, 7, 6, 4, 4, 10, 4, 1, 8, 11, 4, 4, 3, 6, 6, 5, 4, 8, 4, 2, 5, 13, 4, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,7 REFERENCES H. Cohen, Course in Computational Alg. No. Theory, Springer, 1993, pp. 514-5. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 0..10000 S. R. Finch, Class number theory Steven R. Finch, Class number theory [Cached copy, with permission of the author] Rick L. Shepherd, Binary quadratic forms and genus theory, Master of Arts Thesis, University of North Carolina at Greensboro, 2013. PROG (PARI) a(n)=qfbclassno(n\2*-4-n%2-3) \\ Charles R Greathouse IV, Apr 25 2013 (PARI) a(n)=quadclassunit(n\2*-4-n%2-3).no \\ Charles R Greathouse IV, Apr 25 2013 CROSSREFS Sequence in context: A285202 A004737 A255616 * A165475 A319420 A267134 Adjacent sequences:  A014597 A014598 A014599 * A014601 A014602 A014603 KEYWORD nonn AUTHOR Eric Rains (rains(AT)caltech.edu) STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 15 20:00 EST 2019. Contains 330000 sequences. (Running on oeis4.)