As n does not divide a + b + c, and f is invertible modulo n, n does not
Hypotheses as in
suppose that n does not
divide a + b + c. For each integer 1 < ~ <- n - 1 which is invertible modulo n,
consider the sequence of integers f, f + n, f + 2 n, .
... For all r sufficiently
large, the mapping
for f + r n
p(z(- +)) H~R(X(n; a, b,
By (22.214.171.124), any finite number of elements in
P(z (- O)
HI,,,(X(n; a, b,
may be represented by differentials lying in
C(,b Ix] y++,.
for a suitably large r. By (6.8.3), these elements are linearly dependent
upon the classes of