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FredH
  • Member for 9 years, 2 months
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52 votes

Is there a math expression equivalent to the conditional ternary operator?

50 votes
Accepted

Is there a logarithm base for which the logarithm becomes an identity function?

37 votes

Does $(n+1)(n-2)x_{n+1}=n(n^2-n-1)x_n-(n-1)^3x_{n-1}$ with $x_2=x_3=1$ define a sequence that is integral at prime indices?

15 votes

Is there a simple perfect squaring of a 1366 by 768 rectangle?

8 votes
Accepted

Triple Pythagorean with $a^2+b^2=c^4$

8 votes
Accepted

Integral roots of cubic equation $x^3-27x+k=0$

7 votes
Accepted

Prove that there are an infinite amount of positive square free integers $n$ such that $n\mid2015^n-1$

7 votes

The number of elements not in conjugate of a subgroup

7 votes
Accepted

Existence of 3 natural numbers that divide each other when squared and have 1 taken away from them

6 votes

Find all positive integer $a,b$ such that $a^3-b^7=a-b$

6 votes
Accepted

$A^X+B^Y=C^Z\pm 1$ Beal's conjecture "almost" solutions

5 votes
Accepted

Integers which can be written as sum of powers of $2,3$, and $5$

5 votes
Accepted

For any $k \in \mathbb{N}$, there exist $s \in \mathbb{N}$ such that the expression $9s+3+2^{k}$ is a power of $2$

5 votes
Accepted

Proving magic squares determinant is a multiple of 3 when any numbers can be used

5 votes
Accepted

Is a semigroup with unique right identity and left inverse a group?

5 votes
Accepted

if $G$ is a divisible group then any subgroup of $G$ is also divisible

4 votes
Accepted

Can the smallest solution of $\varphi(k)=n$ be an even positive integer?

4 votes
Accepted

If $u^3+v+w=x+y^2+z^2,u+v^3+w=x^2+y+z^2,u+v+w^3=x^2+y^2+z,$ prove the following

3 votes
Accepted

Convert to polar coordinates, where 0 degrees means x = 0 and y > 0, increasing clockwise.

3 votes
Accepted

For any eight points on an equilateral triangle of side $1$, there's at least one pair of those points at most $1/3$ apart

3 votes
Accepted

Number of solutions of $x^e \equiv c \mod p$

3 votes

Arrange the numbers in the given rectangular blocks

3 votes
Accepted

existence of identity for a binary operation

3 votes
Accepted

Which even bases do self "dividing" numbers exist?

3 votes

All positive solutions of $\tan x=x$

3 votes
Accepted

A question about the famous paper that finds solutions for $33=x^3+y^3+z^3$

3 votes
Accepted

Clarification about Carmichael's Lambda Function

3 votes

Finding place of the nine digits

3 votes

inverse of $y=\frac{x}{\log{x}}$?

3 votes
Accepted

Let $G$ be a finite simple group and let $H\subset G$ be a abelian subgroup of index $|G:H|=p$. Prove that $H = \{e\}$.