

A091404


Numbers n such that genus of group Gamma_0(n) is 2.


4




OFFSET

1,1


COMMENTS

I assume it is known that there are no further terms? A reference for this would be nice.


REFERENCES

B. Schoeneberg, Elliptic Modular Functions, SpringerVerlag, NY, 1974, p. 103.
G. Shimura, Introduction to the Arithmetic Theory of Automorphic Functions, Princeton, 1971, see Prop. 1.40 and 1.43.


LINKS

Table of n, a(n) for n=1..8.


FORMULA

Numbers n such that A001617(n) = 2.


CROSSREFS

Cf. A001617, A001615, A000089, A000086, A001616, A091401, A091403.
Sequence in context: A092624 A254751 A260993 * A260994 A114963 A146755
Adjacent sequences: A091401 A091402 A091403 * A091405 A091406 A091407


KEYWORD

nonn,fini,full


AUTHOR

N. J. A. Sloane, Mar 02 2004


STATUS

approved



