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A113241
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Sum{k=1..n, tau(2k)-1}.
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0
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0, 1, 3, 6, 9, 12, 17, 20, 24, 29, 34, 37, 44, 47, 52, 59, 64, 67, 75, 78, 85, 92, 97, 100, 109, 114, 119, 126, 133, 136, 147, 150, 156, 163, 168, 175, 186, 189, 194, 201, 210, 213, 224, 227, 234, 245, 250, 253, 264, 269, 277, 284, 291, 294, 305, 312, 321, 328
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OFFSET
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0,3
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1/(1-x)) Sum_{k>0} x^k(1-x^(3k))/((1-x^k)(1-x^(2k))); a(n)=sum{k=1..n, tau(2k)}-n.
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MATHEMATICA
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CoefficientList[ Series[ Sum[x^k(1 - x^(3k))/((1 - x^k)(1 - x^(2k))), {k, 60}], {x, 0, 57}]/(1 - x), x]
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CROSSREFS
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KEYWORD
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easy,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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