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 A106029 a(n) is the number of orbits under the action of GL_2[Z] on the primitive binary quadratic forms of discriminant D, where D=m if m=1 (mod 4), D=4*m otherwise and m<0 is the n-th squarefree number. 0
 1, 1, 1, 2, 2, 1, 2, 1, 2, 3, 2, 3, 1, 4, 2, 2, 4, 4, 4, 2, 4, 3, 2, 2, 4, 3, 5, 4, 1, 3, 3, 2, 4, 3, 4, 2, 2, 4, 5, 6, 6, 1, 6, 4, 4, 3, 6, 6, 4, 3, 3, 2, 4, 6, 4, 7, 2, 4, 5, 5, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS A000924 is the same except it is under the action of SL_2[Z]. LINKS Table of n, a(n) for n=1..61. S. R. Finch, Class number theory Steven R. Finch, Class number theory [Cached copy, with permission of the author] Jens Jonasson, Classes of integral binary quadratic forms, Master's thesis (2001), Appendix B. EXAMPLE m = -1, -2, -3, -5, -6, -7, -10, -11, -13, ... with corresponding discriminant D = -4, -8, -3, -20, -24, -7, -40, -11, -52, .... CROSSREFS Cf. A000924. Sequence in context: A024880 A029424 A061498 * A260311 A188431 A105153 Adjacent sequences: A106026 A106027 A106028 * A106030 A106031 A106032 KEYWORD nonn AUTHOR Steven Finch, May 05 2005 STATUS approved

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Last modified February 24 22:04 EST 2024. Contains 370307 sequences. (Running on oeis4.)