arXiv math/05063852005-06-20math.CA

Ramanujan's Inverse Elliptic Arc Approximation

Mark B. Villarino

备注：: Four pages

英文摘要：

We suggest a continued fraction origin to Ramanujan's approximation to {(a-b)/(a+b)}^2 in terms of the arc length of an ellipse with semiaxes a and b. Moreover, we discuss the asymptotic accuracy of the approximation.

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