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A280097
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Sum of the divisors of 24*n - 1.
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3
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24, 48, 72, 120, 144, 168, 168, 192, 264, 240, 264, 336, 312, 408, 360, 384, 456, 432, 672, 480, 504, 576, 600, 744, 600, 720, 648, 744, 840, 720, 744, 840, 912, 984, 840, 864, 888, 912, 1296, 1104, 984, 1080, 1032, 1272, 1176, 1104, 1368, 1152, 1488, 1320, 1224, 1320, 1344, 1824, 1320
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OFFSET
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1,1
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COMMENTS
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All terms are multiples of 24 [Gupta, Sierpinski]. - Vincenzo Librandi, Apr 07 2011
Note that 24n - 1 is also the denominator of the Bruinier-Ono finite algebraic formula for the number of partitions of n (Cf. A183010).
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LINKS
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FORMULA
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Sum_{k=1..n} a(k) = c * n^2 + O(n*log(n)), where c = 4*Pi^2/3 = 13.159472... . - Amiram Eldar, Mar 28 2024
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EXAMPLE
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For n = 5 we have that 24*5 - 1 = 119, and the sum of the divisors of 119 is 1 + 7 + 17 + 119 = 144, so a(5) = 144.
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MATHEMATICA
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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