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Results tagged with ca.classical-analysis-and-odes
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user 1859
Special functions, orthogonal polynomials, harmonic analysis, ordinary differential equations (ODE's), differential relations, calculus of variations, approximations, expansions, asymptotics.
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vote
When does 'positive' imply 'sum of squares'?
I believe another recent question contains an answer:
Hilbert's 17th problem asked if a nonnegative real polynomial is the sum of squares of rational functions. It was answered affirmative by Art …