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A064888 Numerators of partial sums of 1/A051451. 1

%I #7 Mar 18 2018 04:08:09

%S 1,2,3,23,323,647,971,7121,6943,185147,363173,179407463,412637165,

%T 20631858251,140035237,3716297449,27822060851939,2853544702763,

%U 58823785801243,568431869527163,279209361758899949,4944838261875010691

%N Numerators of partial sums of 1/A051451.

%C A051451 unlike A003418 contains distinct values of lcm(1..m).

%F a(n) = Sum_{k=1..n} 1/A051451(k), where A051451 is the lcm(1...m), m is a prime or true power of prime. The sequence is convergent.

%e n=6, s(n) = 1/2 + 1/6 + 1/12 + 1/60 + 1/420 + 1/840 = 646/840 = 323/420, the numerator is a(6)=323.

%t s=Select[Range[a, b], Equal[Length[FactorInteger[ # ]], 1]&] a(m) = Apply[LCM, Table[Part[s, w], {w, 1, m}]]

%Y Cf. A003418, A051451, A064857-A064859.

%K frac,nonn

%O 1,2

%A _Labos Elemer_, Oct 10 2001

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Last modified April 19 15:11 EDT 2024. Contains 371794 sequences. (Running on oeis4.)