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 A115964 Denominator of sum_{i=1..n} 1/prime(i)^3. 6
 8, 216, 27000, 9261000, 12326391000, 27081081027000, 133049351085651000, 912585499096480209000, 11103427767506874702903000, 270801499821725167129101267000, 8067447481189014453943055845197000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numerators are in A115963. Also the primorials cubed. - Reikku Kulon, Sep 18 2008 LINKS FORMULA a(n) = denominator of sum_{i=1..n} 1/A000040(i)^3. a(n) = A002110(n)^3. - Reikku Kulon, Sep 18 2008 EXAMPLE 1/8, 35/216, 4591/27000, 1601713/9261000, 2141141003/12326391000, 4716413174591/27081081027000. MATHEMATICA a[n_]:=Product[Prime[i]^3, {i, 1, n}]; (* Vladimir Joseph Stephan Orlovsky, Dec 05 2008 *) CROSSREFS Cf. A115963 (numerators). Cf. A024451 (numerator of sum_{i=1..n} 1/prime(i)), A002110 (primorial, also denominator of sum_{i=1..n} 1/prime(i)), A061015 (numerator of sum_{i=1..n} 1/prime(i)^2). Cf. A000040, A075986/A075987, A106830/A034386. Cf. A061742, A100778. - Reikku Kulon, Sep 18 2008 Sequence in context: A000442 A268471 A226524 * A245591 A247539 A188680 Adjacent sequences:  A115961 A115962 A115963 * A115965 A115966 A115967 KEYWORD easy,frac,nonn AUTHOR Jonathan Vos Post, Mar 14 2006 STATUS approved

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Last modified December 16 04:05 EST 2019. Contains 330013 sequences. (Running on oeis4.)