joriki

Berlin, Germany

Age: 43

top accounts reputation activity favorites subscriptions

an integer sum of products of tangents

sequences-and-series trigonometry asked Jul 21 '12 at 21:38

math.stackexchange.com

13 votes

A proof of Wolstenholme's theorem

number-theory binomial-coefficients alternative-proof asked Jul 16 '12 at 10:43

math.stackexchange.com

12 votes

necessary and sufficient condition for trivial kernel of a matrix over a commutative ring

linear-algebra abstract-algebra matrices ring-theory asked Oct 11 '11 at 16:07

math.stackexchange.com

11 votes

Arnol'd's trivium problem #68

optimization calculus-of-variations asked Oct 14 '12 at 13:19

math.stackexchange.com

10 votes

definite and indefinite sums and integrals

soft-question integration summation asked Oct 14 '12 at 12:55

math.stackexchange.com

9 votes

How to evaluate $\displaystyle\int_0^1\frac{\log^2(1+x)}x\mathrm dx$?

sequences-and-series integral definite-integral asked Feb 28 at 10:19

math.stackexchange.com

7 votes

variable bounds on definite integrals in Wolfram|Alpha

wolfram-alpha asked Jul 13 '11 at 11:24

math.stackexchange.com

6 votes

Is there a connection between the 3D random walk constant and the partition function?

stochastic-processes partitions random-walk asked Dec 26 '11 at 1:13

math.stackexchange.com

5 votes

expansion of $\int_0^\infty\left(\frac{\sin t}t\right)^p\mathrm dt$ in inverse powers of $p$

sequences-and-series convergence asymptotics definite-integral asked May 8 '12 at 16:07

math.stackexchange.com

5 votes

What's up with Plouffe's inverter? Is there an alternative?

online-resources asked Oct 24 '12 at 9:58

math.stackexchange.com

Top Answers

138

Self-Contained Proof that $\sum\limits_{n=1}^{\infty} \frac1{n^p}$ Converges for $p > 1$

math.stackexchange.com

Deleting any digit yields a prime… is there a name for this?

math.stackexchange.com

Multiple-choice question about the probability of a random answer to itself being correct

math.stackexchange.com

For which number does multiplying it by 99 add a 1 to each end of its decimal representation?

math.stackexchange.com

What's the largest possible volume of a taco, and how do I make one that big?

math.stackexchange.com

Volume of Region in 5D Space

math.stackexchange.com

How to answer a student objection to the use of “of” in pronouncing f(x)?

math.stackexchange.com

What are the Axiom of Choice and Axiom of Determinacy?

math.stackexchange.com

Is that true that all the prime numbers are of the form $6m \pm 1$?

math.stackexchange.com

“Casual” mathematical facts with practical consequences

math.stackexchange.com

What is wrong in my proof that 90 = 95? Or is it correct?

math.stackexchange.com

Has any previously unknown result been proven by an automated theorem prover?

math.stackexchange.com

lim (a + b) when lim(b) does not exist?

math.stackexchange.com

$\sum\limits_{k=1}^{\infty} {1 \over k}{1 \over 2k-1}$ how to show that this is $ 2 \ln 2 $?

math.stackexchange.com

“How long 'til we get there?” Road trip puzzle

math.stackexchange.com

Find a way from 2011 to 2 in four steps using a special movement

math.stackexchange.com

You see a route 14 bus on the moon. What is the most likely number of bus routes on the moon?

math.stackexchange.com

Sequence of powers of Gaussian integers capturing all positive integers?

math.stackexchange.com

Is it possible for a function to be in $L^p$ for only one $p$?

math.stackexchange.com

Proving $\sum\limits_{l=1}^n \sum\limits _{k=1}^{n-1}\tan \frac {lk\pi }{2n+1}\tan \frac {l(k+1)\pi }{2n+1}=0$

math.stackexchange.com

Can you prove why consecutive diagonal intersection points show decreasing fractions inside a rectangle?

math.stackexchange.com

Not lifting your pen on the $n\times n$ grid

math.stackexchange.com

What are the 2125922464947725402112000 symmetries of a Rubik's Cube?

math.stackexchange.com

Why is $\tan$ so different from $\sin$ & $\cos$?

math.stackexchange.com

Symmetries of Cube

math.stackexchange.com

Residue of $z^2 e^{1/\sin z}$ at $z=\pi$

math.stackexchange.com

Rain droplets falling on a table

math.stackexchange.com

Calculating the probability of seeing a shooting star within half an hour if we know it for one hour

math.stackexchange.com

Group of positive rationals under multiplication not isomorphic to group of rationals

math.stackexchange.com

Largest sphere in a “grid graph”

math.stackexchange.com