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a(n) = the denominator of (Sum_{k=1..n} 1/A134411(k)).
2

%I #8 Sep 16 2015 13:40:30

%S 1,1,1,2,6,6,6,6,6,3,6,6,6,3,12,12,12,12,12,12,12,12,4,4,4,12,12,12,3,

%T 2,2,6,6,6,3,24,8,8,24,24,24,24,24,24,24,24,8,8,40,40,120,120,120,120,

%U 120,120,120,120,40,40,40,120,120,120,120,120,120,120,120

%N a(n) = the denominator of (Sum_{k=1..n} 1/A134411(k)).

%t a = {1}; s = 1; Do[i = 1; While[ ! PrimeQ[Numerator[s + 1/i]], i++ ]; s = s + 1/i; AppendTo[a, Denominator[s]], {80}]; a (* _Stefan Steinerberger_, Oct 27 2007 *)

%Y Cf. A134411, A134412.

%K frac,nonn

%O 1,4

%A _Leroy Quet_, Oct 24 2007

%E More terms from _Stefan Steinerberger_, Oct 27 2007