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A257603 Maximal squarefree f such that the congruence subgroup Gamma_0(f)+ has genus n. 1
119, 238, 390, 510, 570, 910, 858, 897, 1190, 1365, 1326, 1518, 2310, 1870, 2730, 2002, 2145, 2046, 2415, 3570, 3003, 2926, 3135, 3990, 3255, 2670, 4290, 3315, 4830, 3198, 5610, 3927, 3910, 6006, 4641, 6270, 4270, 5005, 6630, 6510, 5313, 5187, 6045, 7590, 4758, 7854, 5565, 7770, 6783 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

N. J. A. Sloane, Table of n, a(n) for n = 0..100 [Extracted from the Cummins paper]

C. J. Cummins, Congruence subgroups of groups commensurable with PSL(2, Z) of genus 0 and 1, Experiment. Math. Volume 13, Issue 3 (2004).

C. J. Cummins, Tables accompanying previous paper

CROSSREFS

Sequence in context: A255580 A227515 A207059 * A063348 A243581 A103852

Adjacent sequences:  A257600 A257601 A257602 * A257604 A257605 A257606

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 07 2015

STATUS

approved

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Last modified December 6 19:31 EST 2019. Contains 329809 sequences. (Running on oeis4.)