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A111248
Dimension of the space of weight 2 modular forms for Gamma_0(n).
2
0, 1, 1, 2, 1, 3, 1, 3, 3, 3, 2, 5, 1, 4, 4, 5, 2, 7, 2, 6, 4, 5, 3, 8, 5, 5, 6, 7, 3, 10, 3, 8, 6, 6, 6, 12, 3, 7, 6, 10, 4, 12, 4, 9, 10, 8, 5, 14, 8, 13, 8, 10, 5, 15, 8, 12, 8, 9, 6, 18, 5, 10, 12, 14, 8, 16, 6, 12, 10, 16, 7, 20, 6, 11, 16, 13, 10, 18, 7, 18, 15, 12, 8, 22, 10, 13, 12, 16, 8, 26
OFFSET
1,4
COMMENTS
Equivalently, this is the dimension of the space of level n, weight 2 modular forms. - Steven Finch, Apr 03 2009
LINKS
S. R. Finch, Modular forms on SL_2(Z), December 28, 2005. [Cached copy, with permission of the author]
FORMULA
a(n) = A001617(n) + A001616(n) - 1. - Steven Finch, Apr 03 2009
PROG
(Magma) [ Dimension(ModularForms(Gamma0(n), 2)) : n in [1..100] ]; // Klaus Brockhaus, Mar 10 2011
CROSSREFS
Cf. A001616, A001617. [Steven Finch, Apr 03 2009]
Cf. A006571.
Sequence in context: A145652 A373745 A368290 * A100714 A339364 A050123
KEYWORD
nonn
AUTHOR
Steven Finch, Oct 31 2005
EXTENSIONS
More terms from Steven Finch, Apr 03 2009
STATUS
approved