Let $f$ be a $1$-Lipschitz function on the interval $[0,1]$. Then, by Jackson's theorem we get that there exists a polynomial $P_n$ of degree $n$ such that $$ |f(x)-P_n(x)|=O\!\left(\frac{1}{n}\right).$$ Let $\boldsymbol{a}$ denote that vector of $n+1$ coefficients $a_i$, $i=0,\ldots,n$, of $P_n$. I am interested in bounding $\Vert\boldsymbol{a}\Vert_1$. Are there any known results on this?
1 Answer
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I have found this question and references therein which answers my above question