>>532
＜メモ＞
余談ですが
下記のBernoulli number ”6.5 Use in topology”
によれば、「ES_n ＝ 2^{2n-2} - 2^{4n-3}) Numerator (B_{4n}/{4n}).」という式があるらしいね

（参考）
https://en.wikipedia.org/wiki/Bernoulli_number#Use_in_topology
Bernoulli number

Contents
6 Applications of the Bernoulli numbers
6.5 Use in topology

Use in topology
The Kervaire–Milnor's formula for the order of the cyclic group of diffeomorphism classes of exotic (4n − 1)-spheres which bound parallelizable manifolds involves Bernoulli numbers. Let ESn be the number of such exotic spheres for n ＞＝ 2, then
ES_n ＝ 2^{2n-2} - 2^{4n-3}) Numerator (B_{4n}/{4n}).
The Hirzebruch signature theorem for the L genus of a smooth oriented closed manifold of dimension 4n also involves Bernoulli numbers.