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Lee, Elvin (1969). «On Divisibility by Nine of the Sums of Even Amicable Pairs». Mathematics of Computation23 (107): 545-548. ISSN0025-5718. JSTOR2004382. doi:10.2307/2004382.
Lee, Elvin (1969). «On Divisibility by Nine of the Sums of Even Amicable Pairs». Mathematics of Computation23 (107): 545-548. ISSN0025-5718. JSTOR2004382. doi:10.2307/2004382.
renyi.hu
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