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A244576
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Sum of all proper divisors of all positive integers <= prime(n).
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3
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0, 0, 2, 7, 23, 38, 69, 89, 133, 227, 268, 397, 483, 536, 632, 821, 1018, 1125, 1355, 1511, 1633, 1890, 2077, 2406, 2906, 3150, 3263, 3509, 3680, 3960, 5026, 5319, 5854, 6003, 6909, 7130, 7761, 8345, 8681, 9381, 9986, 10351, 11456, 11771, 12212, 12481, 14128
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OFFSET
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1,3
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COMMENTS
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Also sum of all proper divisors of all positive integers <= prime(n)-1.
Also zero together with the numbers that are repeated in A244049.
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LINKS
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FORMULA
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a(n) ~ (Pi^2/12 - 1/2) * n^2 * log(n)^2. - Amiram Eldar, Mar 22 2024
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PROG
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(PARI) a(n) = sum(i=2, prime(n), sigma(i)-i-1); \\ Michel Marcus, Sep 29 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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