123,641 reputation
8117239
bio website von-eitzen.de/math/tntrep.xml
location Bonn, Germany
age 48
visits member for 2 years, 3 months
seen yesterday

I did study math and had a knack for it, but I am sooo out of that business now ...


Dec
16
revised Proofs involving positive real numbers
added 5 characters in body
Dec
16
reviewed Close How to solve $\sin(\arctan((\frac{1}{2}))$
Dec
16
reviewed Looks OK Every Regular Language is a Context Free Language
Dec
16
reviewed No Action Needed Finding representation matrix of $M$*$(K_5)$ above $\mathbb F_2$
Dec
16
reviewed No Action Needed Eigenvalue inequalities for Hermitian matrices
Dec
16
reviewed No Action Needed Finding the total number of members in a club with multiple committees
Dec
16
reviewed Leave Open Can there be a bijection between a countably infinite set and an uncountably infinite set?
Dec
16
reviewed Close Which one is correct option?
Dec
16
reviewed Close Complex Analysis analytic function 1$f(z)=z$
Dec
16
reviewed Close if $f'(x) = -8xe^{x^2}$ and $f(0)=3$ then $f(x) =$?
Dec
16
comment if $f'(x) = -8xe^{x^2}$ and $f(0)=3$ then $f(x) =$?
Wc ould check yur answers if you gave them here
Dec
16
comment Choosing primes uniformly at random
"Close to uniform" is a doubtful claim about nextprime(random()). The chance of picking $p\equiv -1\pmod 6$ in $[10^7,5\cdot 10^7]$ with this is $0.51294$ instead of $0.499996$, which is slightly significant (and a consequence of there not being anyprime $\equiv 3\pmod 6$)
Dec
15
comment Why is this combinatoric solution not correct?
And once you have done that, you count each valid configuration repeatedly. E.g. "violet to A, then blue to C, then red to B, then yellow to D, then the rest somehow" is the same as "violet to A, then red to B, then blue to C, then yellow to D, then the rest somehow", not to mention that the distinction between first four balls and "the rest" leads to even more repeated counting.
Dec
15
revised Showing $\gamma < \sqrt{1/3}$ without a computer
deleted 1 character in body; edited title
Dec
15
reviewed Close PDF of Gamma R.V.
Dec
15
reviewed Close Marriage theorem. Proof.
Dec
15
answered Proofs involving positive real numbers
Dec
15
answered Proving that a function is absolutely monotonic on a given interval
Dec
15
comment Theorem with seemingly reduntant part
Oh, maybe I now see what you mean: Maybe You confuse $u{.}u\ge 0\quad \land \quad(u{.}u=0\Leftrightarrow u=0)$ with $(u{.}u\ge 0\land u{.}u=0)\iff u=0$.
Dec
15
answered Theorem with seemingly reduntant part