Identify the inverse trig function as a hypergeometric function, and manipulate the series expansion of the hypergeometric function. Any book on hypergeometric functions will give the necessary formulae.
Hi:
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Added Nov.3, 2009
(For anyone who can't read the formula below (probably everyone) and who
might have an interest in the subject: - the derivation of two simple equations
that locate all the zeros of the zeta...