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A334764
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a(n) = Product_{k=1..n} d(2*k - 1), where d() is the number of divisors function A000005.
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0
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1, 2, 4, 8, 24, 48, 96, 384, 768, 1536, 6144, 12288, 36864, 147456, 294912, 589824, 2359296, 9437184, 18874368, 75497472, 150994944, 301989888, 1811939328, 3623878656, 10871635968, 43486543872, 86973087744, 347892350976, 1391569403904, 2783138807808, 5566277615616, 33397665693696, 133590662774784
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..33.
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EXAMPLE
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a(3) = d(1)*d(3)*d(5) = 1*2*2 = 4.
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MATHEMATICA
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Rest @ FoldList[Times, 1, DivisorSigma[0, Range[1, 50, 2]]] (* Amiram Eldar, May 10 2020 *)
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PROG
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(PARI) a(n) = prod(k=1, n, numdiv(2*k-1)); \\ Michel Marcus, May 10 2020
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CROSSREFS
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Cf. A000005, A066843, A099774.
Sequence in context: A290859 A290659 A286866 * A218861 A078222 A078223
Adjacent sequences: A334761 A334762 A334763 * A334765 A334766 A334767
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KEYWORD
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nonn
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AUTHOR
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Ctibor O. Zizka, May 10 2020
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STATUS
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approved
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