User Woett

15 votes

What are some examples of ingenious, unexpected constructions?

answered Mar 11, 2012 at 13:55

15 votes

Accepted

Is there an explicit formula for $\sum x^n/(n!)^2$?

answered Apr 15, 2012 at 15:09

14 votes

Awfully sophisticated proof for simple facts

answered Oct 13, 2011 at 3:28

11 votes

Accepted

Squares in an arithmetic progression

answered Mar 30, 2012 at 21:06

11 votes

Object of proven finiteness, yet with no algorithm discovered?

answered Jul 18 at 6:51

10 votes

Can the Riemann hypothesis be undecidable?

answered Nov 1, 2011 at 17:53

9 votes

Are there results in "Digit Theory"?

answered Mar 21, 2013 at 16:06

9 votes

Lagrange four squares theorem

answered Oct 22, 2018 at 9:16

8 votes

Accepted

Product of sum of reciprocals of prime numbers

answered Aug 19, 2019 at 11:20

6 votes

Contest problems with connections to deeper mathematics

answered Dec 22, 2011 at 2:34

6 votes

Finite sums of prime numbers $\geq x$

answered Apr 3, 2012 at 16:11

1 vote

Twin primes and D primes

answered Mar 23, 2012 at 1:38

1 vote

Largest prime divisor of a sum

answered Apr 6, 2011 at 11:59

1 vote

Theorems that are 'obvious' but hard to prove

answered Sep 29, 2011 at 22:47

0 votes

Unconventional types of induction

answered May 11, 2014 at 22:18

Stack Exchange Network

15 Answers

What are some examples of ingenious, unexpected constructions?

Is there an explicit formula for $\sum x^n/(n!)^2$?

Awfully sophisticated proof for simple facts

Squares in an arithmetic progression

Object of proven finiteness, yet with no algorithm discovered?

Can the Riemann hypothesis be undecidable?

Are there results in "Digit Theory"?

Lagrange four squares theorem

Product of sum of reciprocals of prime numbers

Contest problems with connections to deeper mathematics

Finite sums of prime numbers $\geq x$

Twin primes and D primes

Largest prime divisor of a sum

Theorems that are 'obvious' but hard to prove

Unconventional types of induction