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%I #16 Jun 04 2016 07:57:24
%S 121,163,145,241,215,256,175,388,212,403,235,381,198,549,178,485,294,
%T 667,191,647,203,729,284,537,212
%N Number of congruence subgroups of PSL(2,Z) of genus n, up to conjugacy in PGL(2,Z).
%H C. J. Cummins and S. Pauli, <a href="https://www.emis.de/journals/EM/expmath/volumes/12/12.2/pp243_255.pdf">Congruence Subgroups of PSL(2,Z) of Genus Less than or Equal to 24</a>, Experiment. Math. Volume 12, Issue 2 (2003), 243-255. See Table 1.
%Y A258691, A102474, A258693-A258700 give the ten sequences in Table 1 of Cummins and Pauli (2003).
%K nonn,more
%O 0,1
%A _N. J. A. Sloane_, Jun 07 2015