martini
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# 6,275 Actions

 Mar 22 revised convolution: how can I show that $(y*f)'(t) = (y'*f)(t) + y(0)f(t)$ deleted 85 characters in body; edited title Mar 22 answered $\sum_n |x_n||y_n| < \infty$ for all $(x_n) \in l^3$ implies $(y_n) \in l^{3/2}$ Mar 22 comment Is there a group $G$, for every $n>0$, acts on set $\{1, 2, …, n^2\}$ with orbit of size $n$? $[G: Stab(1)]$ is a quotient of $G$, hence smaller then $G$. And no finite number $|G|$ has $|G| \ge n$ for all $n$. Mar 22 revised Is there a group $G$, for every $n>0$, acts on set $\{1, 2, …, n^2\}$ with orbit of size $n$? added 49 characters in body Mar 22 answered Is there a group $G$, for every $n>0$, acts on set $\{1, 2, …, n^2\}$ with orbit of size $n$? Mar 22 answered Given $\Bbb N$ can you reach every infinite cardinal by performing succesive power set operations? Mar 22 answered Showing that the operator norm is equal to the q-norm. Mar 22 revised Show that curve has a constant torsion. deleted 1 character in body Mar 22 comment Show that curve has a constant torsion. Now, but $U := \{\beta\}^\bot$ is a two-dimensional subspace. Any three vectors in $U$ must be dependent. Mar 22 answered Show that curve has a constant torsion. Mar 22 comment Every finite connected space is also path-connected? If $y \in A$, $y' \in U_y$, there is a sequence for $y$, $x_0=x, \ldots, x_n = y$. But then $x_0 = x, \ldots, x_n = y, x_{n+1} = y'$ is a sequence for $y'$. If $z' \in U_z$ and $z' \in A$, say $x_0 = x, \ldots , x_n = z'$ were a sequence for $z'$, then $x_0 = x, \ldots, x_n = z', x_{n+1} = z$ were a sequence for $z$. Contradiction. Hence $z' \not\in A$. Mar 22 answered $A$ does not reverse the sign of any vector iff $A^{T}$ does not. Mar 22 answered Differentiation of a measure Mar 22 reviewed Leave Open Maple - PDE substitution Mar 22 reviewed Leave Open How can I show that the stochastic process $M_t = W_t^3 – 3t W_t$ is a martingale $\mathbb{E}[M_u|F_t]$? Mar 22 reviewed Leave Open Laplace Transform: $g(x)=a\sin(x)+\int_0^x \sin(x-u)g(u) du$ Mar 22 reviewed Leave Open How can this improper integral be solved Mar 22 reviewed Leave Open Division polynomial by polynomial with 2 variables Mar 22 reviewed Close Find the closed formula for following problem. Mar 22 reviewed No Action Needed Ring of all $\mathbb{C}$-valued continuous functions on closed interval Noetherian?