Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #23 Sep 08 2022 08:45:20
%S 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,
%T 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,
%U 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
%N Dimension of the space of weight 2 modular forms for Gamma_0(n).
%C Equivalently, this is the dimension of the space of level n, weight 2 modular forms. - _Steven Finch_, Apr 03 2009
%H Klaus Brockhaus, <a href="/A111248/b111248.txt">Table of n, a(n) for n = 1..10000</a>
%H S. R. Finch, <a href="/A000521/a000521_1.pdf">Modular forms on SL_2(Z)</a>, December 28, 2005. [Cached copy, with permission of the author]
%F a(n) = A001617(n) + A001616(n) - 1. - _Steven Finch_, Apr 03 2009
%o (Magma) [ Dimension(ModularForms(Gamma0(n), 2)) : n in [1..100] ]; // Klaus Brockhaus, Mar 10 2011
%Y Cf. A001616, A001617. [_Steven Finch_, Apr 03 2009]
%Y Cf. A006571.
%K nonn
%O 1,4
%A _Steven Finch_, Oct 31 2005
%E More terms from _Steven Finch_, Apr 03 2009