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A064889 Denominators of partial sums of reciprocals of A051451 (A051451 includes lcm(1,...,x), x=power of prime from A000961 and also contains 1). 0

%I #11 Mar 18 2018 09:42:58

%S 1,2,3,4,30,420,840,1260,9240,9009,240240,471240,232792560,535422888,

%T 26771144400,181704600,4822131600,36100888223400,3702655202400,

%U 76327592243760,737576396429600,362291852261631600,6416241209619040800

%N Denominators of partial sums of reciprocals of A051451 (A051451 includes lcm(1,...,x), x=power of prime from A000961 and also contains 1).

%F a(n) = denominator(Sum_{k=1..n} 1/A051451(k)).

%e n=6, sum = (1/1) + (1/2) + (1/6) + (1/12) + (1/60) + (1/420) = 743/420, the denominator = a(6) = 743. Remark: If 1 is omitted from A051451, the denominators of partial sums of reciprocals do not change; however, numerators are changing, not compatible with these denominators (see A064888).

%Y Cf. A051451, A003418, A000961, A064857, A064858, A064859, A064888, A064890.

%K frac,nonn

%O 1,2

%A _Labos Elemer_, Oct 11 2001

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Last modified March 28 12:26 EDT 2024. Contains 371254 sequences. (Running on oeis4.)