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Denominator of Sum_{i=1..n} 1/prime(i)^3.
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%I #13 Apr 06 2023 06:23:22

%S 8,216,27000,9261000,12326391000,27081081027000,133049351085651000,

%T 912585499096480209000,11103427767506874702903000,

%U 270801499821725167129101267000,8067447481189014453943055845197000

%N Denominator of Sum_{i=1..n} 1/prime(i)^3.

%C Numerators are in A115963.

%C Also the primorials cubed. - _Reikku Kulon_, Sep 18 2008

%F a(n) = denominator of Sum_{i=1..n} 1/A000040(i)^3.

%F a(n) = A002110(n)^3. - _Reikku Kulon_, Sep 18 2008

%e 1/8, 35/216, 4591/27000, 1601713/9261000, 2141141003/12326391000, 4716413174591/27081081027000.

%t a[n_]:=Product[Prime[i]^3, {i, 1, n}]; (* _Vladimir Joseph Stephan Orlovsky_, Dec 05 2008 *)

%Y Cf. A115963 (numerators).

%Y 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).

%Y Cf. A000040, A075986/A075987, A106830/A034386.

%Y Cf. A061742, A100778. - _Reikku Kulon_, Sep 18 2008

%K easy,frac,nonn

%O 1,1

%A _Jonathan Vos Post_, Mar 14 2006