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 Sep 11 awarded Popular Question Aug 26 awarded Yearling May 19 awarded Critic Nov 4 awarded Commentator Nov 4 comment Are all mathematicians human calculators? Damn it Jim, I'm a mathematician, not an accountant. May 16 comment Rationalizing Denominators with Radicals possible duplicate of Rationalize the Denominator by Default Aug 19 awarded Teacher Aug 19 answered I want to find out the angle for the expression $a^3 + b^3 = c^3$. Apr 26 awarded Editor Apr 26 revised Determine the coefficients of an unknown black-box polynomial Minor fix to equations so they work Apr 26 accepted Determine the coefficients of an unknown black-box polynomial Apr 26 suggested approved edit on Determine the coefficients of an unknown black-box polynomial Apr 24 comment Determine the coefficients of an unknown black-box polynomial This seems to work: $X_k=p\left(\exp\left(-\frac{2\pi ik}{n+1}\right)\right), k=0,\dots,n$ and $c_j=\frac1{n+1}\sum\limits_{k=0}^{n-1} X_k \exp\left(\frac{2\pi i jk}{n+1}\right), j=0,\dots,n$ Apr 23 comment Determine the coefficients of an unknown black-box polynomial @J.M. I just tried a few known test polynomials and threw them at the formulae for $X_k$ and $c_j$. It only worked when $a_0 = 0$. On further inspection it looks like $c_0 = c_n = a_0 + a_n$. Apr 23 comment Determine the coefficients of an unknown black-box polynomial Method 1 works only if you don't have a constant term in your polynomial, but that's easy enough to filter out. Are there any conditions on method 2 I should be aware of before I try it out? Apr 20 asked Determine the coefficients of an unknown black-box polynomial Apr 10 comment Spread out the zeros in a binary sequence This works excellently. Just an additional note, one needs $a_0 = 1$. Apr 10 accepted Spread out the zeros in a binary sequence Apr 10 comment Spread out the zeros in a binary sequence @BrianM.Scott That sounds good in a general interpretation, but I wouldn't want to comment if you are talking about applying statistics. Apr 10 comment Spread out the zeros in a binary sequence It's probably more like the sum of the distances, or the mean. For a small fraction you're undoubtedly going to have the minimum distance to be 1, but that doesn't mean they should all be 1. Feel free to make it more precise by interpreting the description!