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T. "Further Lemmata. Proofs of Selberg's Formula." §73 in Introduction
to Number Theory. New York: Wiley, pp. 279-280 and 283-286, 1951.Selberg,
A. "An Elementary Proof of the Prime Number Theorem." Ann. Math.50,
305-313, 1949.Sloane, N. J. A. Sequence A109507
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