7105 Riemann's condition
ᐥLet f be defined and bounded on [a,b]. Then f is Riemann integrable on [a,b] if and only if for every ε>0 there exists a partition P of [a,b] such that inf「sup(f(x))ƧP[a,b]」 − sup「inf(f(x))ƧP[a,b]」 < ε.ᐥ ...
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