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A230294
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a(n) = Sum_{i=1..n} d(4*i+1) - Sum_{i=1..n} d(2*i+1), where d(n) = A000005(n).
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8
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0, 1, 1, 0, 2, 3, 1, 3, 3, 1, 5, 5, 3, 5, 5, 5, 5, 5, 5, 8, 10, 6, 8, 7, 5, 11, 9, 7, 11, 12, 10, 10, 12, 10, 12, 14, 10, 12, 12, 11, 17, 16, 14, 16, 14, 14, 18, 18, 14, 16, 18, 14, 16, 18, 18, 25, 23, 19, 19, 18, 20, 20, 22, 20, 24, 24, 18, 24, 24, 22, 26, 25, 21, 27, 29, 27, 27, 27, 25, 25, 29, 25, 29, 28, 26, 32
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OFFSET
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1,5
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LINKS
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FORMULA
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a(n) = (log(2)/2) * n + O(n^(1/3)*log(n)). - Amiram Eldar, Apr 12 2024
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MAPLE
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MATHEMATICA
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Accumulate[Table[DivisorSigma[0, 4*n + 1] - DivisorSigma[0, 2*n + 1], {n, 1, 100}]] (* Amiram Eldar, Apr 12 2024 *)
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PROG
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(PARI) vector(100, n, sum(i=1, n, numdiv(4*i+1)) - sum(i=1, n, numdiv(2*i+1))) \\ Michel Marcus, Oct 09 2014
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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