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Carl Schildkraut's user avatar
Carl Schildkraut's user avatar
Carl Schildkraut's user avatar
Carl Schildkraut
  • Member for 8 years, 10 months
  • Last seen this week
38 votes
Accepted

Why I can't divide by y in this equation: 4y = y?

34 votes

Sequence that is neither increasing, nor decreasing, yet converges to 1

33 votes
Accepted

Is this proposed method of finding primes valid? If so, would it be effective?

30 votes
Accepted

Is multiplication of two complex numbers that are inside a complex regular polygon still in this polygon?

25 votes
Accepted

Prove $\left|1+z_1\right| +\left|1+z_2 \right| + \left|1+z_1z_2\right|\geq 2$

22 votes

Does there exist a bivariate polynomial that is positive exclusively in the 1st quadrant?

22 votes

Is any mathematican more famous for their conjecture(s) than their theorem(s)?

20 votes
Accepted

Product of areas in a disk

19 votes
Accepted

Under the which condition, factorisation of $a_1^n+a_2^n+\cdots+a_n^n-na_1a_2a_3...a_n ?$ is possible?

18 votes
Accepted

Conjectured connection between $e$ and $\pi$ in a semidisk.

16 votes

Evaluating $\int_0^1\int_0^1\cdots\int_0^1\frac{n\max\{x_1,x_2,\cdots,x_n\}}{x_1+x_2+\cdots+x_n}dx_1dx_2\cdots dx_n$

16 votes
Accepted

$\lim_{n \to \infty}\frac{1}{n}\sum_{k = 1}^nf(k)$ where $f(n)$ is the largest prime factor exponent?

15 votes
Accepted

Is this ambiguity in the use of prime notation to denote a derivative?

15 votes
Accepted

Is there an explicit formula that gives the value of $\sqrt{2+\sqrt{2+\sqrt{2+\cdots}}}$ for $n$ square roots?

15 votes
Accepted

Convergence of $\sum_{n=1}^{\infty} \frac{\sin(n!)}{n}$

13 votes
Accepted

Solutions of $f(x+y^{n})=f(x)+[f(y)]^{n}$.

13 votes
Accepted

Do three consecutive numbers of form $A^2B^3$ exist?

13 votes

Set of primes dividing $2^n+3^n$.

11 votes
Accepted

Non-negative non-decreasing polynomial lower than $x^N$ somewhere in $0 \le x \le 1$

11 votes
Accepted

Infinite product limit

10 votes
Accepted

If $f(a+b)=f(ab)$ for all a and b and $f(\frac{-1}{2})=\frac{-1}{2}$ find $f(1)$

10 votes

Do I need to cite an old theorem, if I've strengthened it, wrote my own theorem statement, with a different proof?

10 votes
Accepted

Find value of $\frac{\sum_{k=1}^{399} \sqrt{20+\sqrt{k}}}{\sum_{k=1}^{399} \sqrt{20-\sqrt{k}}}$

10 votes
Accepted

$AB-BA$ invertible and $A^2+B^2 = AB$ then $3$ divides $n$

10 votes
Accepted

2023 MIT Integration Bee Regular Season Problem 6

9 votes
Accepted

Is there an absolute mimumum distance between zeros of the Riemann zeta function?

9 votes
Accepted

Given an algebraic number $a$, find the closed form of $\arctan (a)$

9 votes
Accepted

Prove that $f(x,y)+f(y,z)\ge f(x,z)$ where $f(x,y)=\sqrt{x\ln x+y\ln y-(x+y)\ln(\frac{x+y}2)}$

9 votes
Accepted

If $\frac{(1+x)^2}{1+x^2}=\frac{13}{37}$, then find the value of $\frac{(1+x)^3}{1+x^3}$

9 votes

Prove the polynomial $x^4+4 x^3+4 x^2-4 x+3$ is positive

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