検索結果- 英語 - 英語
検索内容:
Herbrand-Ribet theorem
name
(mathematics)
A
result
on
the
class
group
of
certain
number
fields,
strengthening
Ernst
Kummer's
theorem
to
the
effect
that
the
prime
p
divides
the
class
number
of
the
cyclotomic
field
of
p-th
roots
of
unity
iff
p
divides
the
numerator
of
the
n-th
Bernoulli
number
Bₙ
for
some
n,
0
<
n
<
p
−
1.
The
Herbrand–Ribet
theorem
specifies
what,
in
particular,
it
means
when
p
divides
such
an
Bₙ.
