The abelianization of the level L mapping class group - [pdf]
[ps]
preprint 2008, submitted.
Abstract :
We calculate the abelianizations of the level $L$ subgroup of the genus $g$ mapping class group
and the level $L$ congruence subgroup of the $2g \times 2g$ symplectic group
for $L$ odd and $g \geq 3$.