Nicolas Essis-Breton
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 Oct 15 comment Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ @joriki I tried to clarified the notation, and you were right for $0 \le k \le 2n$. Thank you. Sorry for the many typos, Fourier analysis is a jungle for which my machete is not sharp yet. Oct 15 revised Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ edit per joriki comment Oct 15 accepted Inequality for term of a positive sequence : show $\frac{1}{n} \ge c_n - c_{n+1} \ge \frac{1}{n+1}$ Oct 15 comment Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ @did The title was inacurrate. Thank you. Oct 15 revised Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ error in title per did comment Oct 15 comment Inequality for term of a positive sequence : show $\frac{1}{n} \ge c_n - c_{n+1} \ge \frac{1}{n+1}$ @sasposcat Good eyes, thanks. Oct 15 revised Inequality for term of a positive sequence : show $\frac{1}{n} \ge c_n - c_{n+1} \ge \frac{1}{n+1}$ typo from saspocat comment Oct 15 revised Inequality for term of a positive sequence : show $\frac{1}{n} \ge c_n - c_{n+1} \ge \frac{1}{n+1}$ typo on sequence space Oct 15 asked Inequality for term of a positive sequence : show $\frac{1}{n} \ge c_n - c_{n+1} \ge \frac{1}{n+1}$ Oct 15 revised Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ g should have been g_n everywhere Oct 15 revised Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ error in the fourier series of g Oct 15 accepted Find an inequality for $\|f\|_p$ when $f=f \chi_E+f\chi_{\tilde E}$ and $m(E)=m(\{x:|f|> 1\})<\infty$ Oct 14 asked Show $\left\lvert \frac{1}{\pi+2} \sum_{0 \le k \le 2n,k\ne n} \frac{i}{k-n} e^{ikt} \right\rvert > c \ln n, c>0$ Oct 14 comment Show $\left\lvert\sum_{k=-n}^n \frac{\sin k t }{k}\right\rvert \le \pi + 2$ for all $n$ and $t$, $t \in [0,2\pi]$ How do you get the bound on $\sin x$ and the bound on the last integral? Oct 14 asked Derivating $f(t)=\int_0^t x dx$ using measure theory Oct 14 asked Convergence of the Fourier series of $f(t)=(t-\pi)\chi_{\left(0,2\pi\right)}$ Oct 13 revised Show $\left\lvert\sum_{k=-n}^n \frac{\sin k t }{k}\right\rvert \le \pi + 2$ for all $n$ and $t$, $t \in [0,2\pi]$ no 2 in the summation Oct 13 revised Show $\left\lvert\sum_{k=-n}^n \frac{\sin k t }{k}\right\rvert \le \pi + 2$ for all $n$ and $t$, $t \in [0,2\pi]$ no -2 in the integral Oct 13 revised Show $\left\lvert\sum_{k=-n}^n \frac{\sin k t }{k}\right\rvert \le \pi + 2$ for all $n$ and $t$, $t \in [0,2\pi]$ a factor of 2 missing in the fourier series Oct 13 revised Show $\left\lvert\sum_{k=-n}^n \frac{\sin k t }{k}\right\rvert \le \pi + 2$ for all $n$ and $t$, $t \in [0,2\pi]$ there was a minus missing in the fourier series