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 Oct 30 revised Evaluate $\int_{-1/2}^{1/2}\frac{\sin^4(n\pi f)}{\lvert\sin(\pi f\lvert^{2d}[\sin(\pi f)]^{2}}df$ for any $d\in(-1/2,1]$ added 4 characters in body Oct 30 comment Evaluate $\int_{-1/2}^{1/2}\frac{\sin^4(n\pi f)}{\lvert\sin(\pi f\lvert^{2d}[\sin(\pi f)]^{2}}df$ for any $d\in(-1/2,1]$ have you tried $\sin x = \tfrac{1}{2}(e^{ix} - e^{-ix})$ ? Oct 30 asked What does $\mathrm{codim} V \ll_\delta 1$ mean if codimension can only be $0$ or $1$? Oct 28 comment Quadratic Sieve I haven't read it in a while: A Tale of Two Sieves Oct 28 answered Fundamental group of the complement of $3$ pairwise linked circles in $\mathbb R^{3}$ Oct 28 comment Finding the closure of sets in different topologies. math.stackexchange.com/a/20650/4997 Oct 28 answered Finding the closure of sets in different topologies. Oct 28 comment Irrationality proofs not by contradiction what kind of assumptions does Gauss lemma make? Oct 20 awarded Nice Question Oct 20 comment Translation of a certain proof of $(\sum k)^2 = \sum k^3$ @mathreadler this is a key point -- I cannot award the bounty without it. we know this formula is more general since the divisor function also does it $\sum \tau(k)^3 = \big(\sum \tau(k)\big)^2$ Possibly this is not true for all $f$ - then just some short explanation of when this works. Oct 18 comment Translation of a certain proof of $(\sum k)^2 = \sum k^3$ OK it's reasonable that $\mathcal{F}(f^3)[0] = \sum f(k)^3$ but can you prove the other side? $$\big[ \mathcal{F}(f)\ast \mathcal{F}(f)\ast\mathcal{F}(f)\big][0] = \big[\sum f(k)\big]^2$$ Oct 18 comment Geometry of nose in and nose out parking in parking lots these kinds of curves appear in contact geometry. See What is a Legendrian Knot? Oct 14 awarded Promoter Oct 13 revised Ideals of $\mathbb{Z}[i]$ geometrically added 236 characters in body Oct 13 answered Ideals of $\mathbb{Z}[i]$ geometrically Oct 6 awarded Custodian Oct 6 revised Where are the roots going? added 357 characters in body Oct 6 answered Where are the roots going? Oct 6 answered Density of the image of the set $\lbrace (x,x), x\in \mathbb{Z} \rbrace$ in $\mathbb{Z_{p}} \times \mathbb{Z}_{q}$ Oct 6 answered Prove that for all $n\in\mathbb{N}$, $\sqrt{n(n+1)}$ is not an integer.