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6 votes

0 answers

515 views

Van der Pol's identity for the sum of divisors and a quartic polynomial equation for odd perfect numbers

asked Sep 25, 2020 at 7:12

5 votes

1 answer

149 views

How does Wolfram Alpha find polynomial equation of given roots?

asked Jun 3, 2022 at 9:44

4 votes

1 answer

291 views

Formulas for $\pi$ of the form $2\sum_{k=0}^\infty\binom{2k}{k}\frac{a^{2k+1}+b^{2k+1}+c^{2k+1}}{4^k(2k+1)}$

asked Jan 6, 2022 at 19:14

3 votes

1 answer

298 views

Some formulas for $\pi$?

asked Jun 25, 2021 at 18:46

3 votes

2 answers

166 views

Using Wikipedia links for natural language processing or how to "solve" a directed graph?

asked Dec 22, 2020 at 8:22

2 votes

1 answer

134 views

Has the diophantine equation $xyz=n(x+y+z)$ for given $n\in \mathbb{N}$ only finitely many solutions $x,y,z\in \mathbb{N}$?

asked Aug 2, 2017 at 13:33

2 votes

1 answer

341 views

Conway's surreal numbers and the Collatz iteration as a game?

asked Nov 3, 2020 at 8:32

2 votes

0 answers

185 views

Twelfth root of two?

asked Apr 25, 2021 at 14:17

1 vote

0 answers

49 views

Is the function $k(g,h) = \frac{1}{1+|gh^{-1}|}$ positive definite?

asked May 4, 2021 at 6:58

1 vote

1 answer

163 views

A followup question on surreal numbers and Collatz iteration game

asked Nov 4, 2020 at 11:11

1 vote

1 answer

80 views

What's wrong with the following definition of $\lim$ and derivative for the surreal numbers?

asked Apr 28, 2022 at 18:58

1 vote

1 answer

183 views

A geometric approach to the odd perfect number problem?

asked Oct 7, 2020 at 8:26

1 vote

1 answer

121 views

A Collatz like function or Eulers totient function vs. the sum of divisors?

asked Oct 30, 2020 at 12:57

1 vote

1 answer

383 views

An recursive formula for the n-th prime?

asked Jan 3, 2021 at 17:08

1 vote

0 answers

46 views

A model of a scale free network based on the divisors of a number which could be analysed mathematically?

asked Jun 19, 2022 at 14:41

1 vote

1 answer

57 views

Is this a $T_1$ topological space and what other properties (or name) does this topological space on the set of prime powers have?

asked Oct 22, 2022 at 19:20

1 vote

0 answers

104 views

Trying to understand / apply the Hilbert–Serre theorem in a specific situation?

asked Jan 5, 2022 at 8:48

0 votes

1 answer

51 views

A version of an algorithm for an "uniform" subset sum problem?

asked Nov 13, 2022 at 16:01

0 votes

2 answers

55 views

Is there a name for $n \times n$ matrices $M$ satisfying $M^2 = n M $?

asked Oct 16, 2022 at 10:34

0 votes

0 answers

125 views

Compute the first two digits of the prime $2^{32582657}-1$

asked Jan 31, 2021 at 18:01

0 votes

0 answers

52 views

How is this type of matrix called?

asked Apr 21, 2021 at 19:11

0 votes

1 answer

177 views

Is a finite group a subgroup of the automorphism group of a variety?

asked Jan 29, 2017 at 17:05

0 votes

1 answer

74 views

Attempt do define a limit of a function for surreal numbers?

asked Apr 29, 2022 at 7:18

0 votes

2 answers

56 views

What is the solution to this matrix optimization problem $A^* = \text{argmin}_{A} \sum_{i=1}^{r-1}|Ax_i-x_{i+1}|^2$?

asked Nov 24, 2021 at 19:27

0 votes

0 answers

43 views

Product representation of some exponential functions?

asked Dec 4, 2021 at 18:04

0 votes

1 answer

55 views

Approximately finding self intersection points of closed plane curves?

asked Nov 12, 2020 at 18:08

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26 Questions

Van der Pol's identity for the sum of divisors and a quartic polynomial equation for odd perfect numbers

How does Wolfram Alpha find polynomial equation of given roots?

Formulas for $\pi$ of the form $2\sum_{k=0}^\infty\binom{2k}{k}\frac{a^{2k+1}+b^{2k+1}+c^{2k+1}}{4^k(2k+1)}$

Some formulas for $\pi$?

Using Wikipedia links for natural language processing or how to "solve" a directed graph?

Has the diophantine equation $xyz=n(x+y+z)$ for given $n\in \mathbb{N}$ only finitely many solutions $x,y,z\in \mathbb{N}$?

Conway's surreal numbers and the Collatz iteration as a game?

Twelfth root of two?

Is the function $k(g,h) = \frac{1}{1+|gh^{-1}|}$ positive definite?

A followup question on surreal numbers and Collatz iteration game

What's wrong with the following definition of $\lim$ and derivative for the surreal numbers?

A geometric approach to the odd perfect number problem?

A Collatz like function or Eulers totient function vs. the sum of divisors?

An recursive formula for the n-th prime?

A model of a scale free network based on the divisors of a number which could be analysed mathematically?

Is this a $T_1$ topological space and what other properties (or name) does this topological space on the set of prime powers have?

Trying to understand / apply the Hilbert–Serre theorem in a specific situation?

A version of an algorithm for an "uniform" subset sum problem?

Is there a name for $n \times n$ matrices $M$ satisfying $M^2 = n M $?

Compute the first two digits of the prime $2^{32582657}-1$

How is this type of matrix called?

Is a finite group a subgroup of the automorphism group of a variety?

Attempt do define a limit of a function for surreal numbers?

What is the solution to this matrix optimization problem $A^* = \text{argmin}_{A} \sum_{i=1}^{r-1}|Ax_i-x_{i+1}|^2$?

Product representation of some exponential functions?

Approximately finding self intersection points of closed plane curves?