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Denominator of partial sums of a certain series.
1

%I #5 May 29 2014 16:28:09

%S 1,33,924,17556,1141140,1025884860,17440042620,715041747420,

%T 16445960190660,115121721334620,345365164003860,1242969225249892140,

%U 382452069307659120,27154096920843797520,1004701586071220508240

%N Denominator of partial sums of a certain series.

%C The numerators are given in A101631.

%F a(n)=denominator(s(n)) with s(n)=24*sum(1/((5*k-1)*k*(5*k+1)), k=1..n).

%t Denominator[24*Accumulate[Table[1/((5k-1)k(5k+1)),{k,15}]]] (* _Harvey P. Dale_, May 29 2014 *)

%K nonn,frac,easy

%O 1,2

%A _Wolfdieter Lang_, Dec 23 2004