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%I #12 May 02 2023 13:10:47
%S -1,13,35,56,77,99,120,141,163,184,205,227,248,269,291,312,333,355,
%T 376,397,419,440,461,483,504,525,547,568,589,611,632,653,675,696,717,
%U 739,760,781,803,824,845,867,888,909,931,952,973,995,1016,1037
%N Dimension of the space of weight n cuspidal newforms for Gamma_1( 27 ).
%H William A. Stein, <a href="http://wstein.org/Tables/dimskg1new.gp">Dimensions of the spaces S_k^{new}(Gamma_1(N))</a>
%H William A. Stein, <a href="http://wstein.org/Tables/">The modular forms database</a>
%F From _Colin Barker_, Feb 24 2015: (Start)
%F a(n) = a(n-1)+a(n-3)-a(n-4) for n>6.
%F G.f.: x^2*(7*x^4+22*x^3+22*x^2+14*x-1) / ((x-1)^2*(x^2+x+1)).
%F (End)
%K sign
%O 2,2
%A _N. J. A. Sloane_, Jul 14 2001