Chitsai Liu's user avatar
Chitsai Liu's user avatar
Chitsai Liu's user avatar
Chitsai Liu
  • Member for 13 years, 10 months
  • Last seen more than 2 years ago
47 votes
1 answer
4k views

How to prove this polynomial always has integer values at all integers?

46 votes
2 answers
5k views

Is the following identity true?

28 votes
9 answers
14k views

Suggestions for good books on class field theory

27 votes
2 answers
2k views

A sum involving roots of unity

20 votes
1 answer
2k views

How to prove that the following double sum is always an integer?

20 votes
1 answer
838 views

A combinatorial identity involving generalized harmonic numbers

15 votes
1 answer
904 views

Prove $4\sum_{k=1}^{p-1}\frac{(-1)^k}{k^2}\equiv 3\sum_{k=1}^{p-1}\frac{1}{k^2}\pmod{p^2}$

15 votes
2 answers
961 views

How to prove $\sum_{k=1}^{\frac{p-1}{2}}\frac{(-1)^k}{k}\sum_{i=\lfloor k/2\rfloor +1}^k\frac{1}{2i-1}\equiv 0\pmod{p}$?

15 votes
2 answers
1k views

A combinatorial identity involving harmonic numbers

1 vote
1 answer
431 views

Integer Polynomial solutions to functional equation