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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
1, 2, 3, 4, 30, 420, 840, 1260, 9240, 9009, 240240, 471240, 232792560, 535422888, 26771144400, 181704600, 4822131600, 36100888223400, 3702655202400, 76327592243760, 737576396429600, 362291852261631600, 6416241209619040800 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = denominator(Sum_{k=1..n} 1/A051451(k)).
EXAMPLE
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).
CROSSREFS
Sequence in context: A354729 A305205 A356905 * A351999 A356885 A057917
KEYWORD
frac,nonn
AUTHOR
Labos Elemer, Oct 11 2001
STATUS
approved

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Last modified March 19 09:40 EDT 2024. Contains 370981 sequences. (Running on oeis4.)