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A334764 a(n) = Product_{k=1..n} d(2*k - 1), where d() is the number of divisors function A000005. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

a(3) = d(1)*d(3)*d(5) = 1*2*2 = 4.

MATHEMATICA

Rest @ FoldList[Times, 1, DivisorSigma[0, Range[1, 50, 2]]] (* Amiram Eldar, May 10 2020 *)

PROG

(PARI) a(n) = prod(k=1, n, numdiv(2*k-1)); \\ Michel Marcus, May 10 2020

CROSSREFS

Cf. A000005, A066843, A099774.

Sequence in context: A290859 A290659 A286866 * A218861 A078222 A078223

Adjacent sequences:  A334761 A334762 A334763 * A334765 A334766 A334767

KEYWORD

nonn

AUTHOR

Ctibor O. Zizka, May 10 2020

STATUS

approved

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Last modified April 16 12:40 EDT 2021. Contains 343037 sequences. (Running on oeis4.)