E706 -- De novo genere serierum rationalium et valde convergentium, quibus ratio peripheriae ad diametrum exprimi potest
(On a new type of rational and highly convergent series, by which the ratio of the periphery to the diameter is able to be expressed)
According to Eneström "Euler starts out with the identity ∫(2 + 2x + x2)/(4 + x2)] dx = arctan[x/(2 - x)].
Originally published in Nova Acta Academiae Scientarum Imperialis Petropolitinae 11, 1798, pp. 150-154
Opera Omnia: Series 1, Volume 16, pp. 21 - 27
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