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A025529 a(n) = (1/1 + 1/2 + ... + 1/n)*LCM{1,2,...,n}. 13
1, 3, 11, 25, 137, 147, 1089, 2283, 7129, 7381, 83711, 86021, 1145993, 1171733, 1195757, 2436559, 42142223, 42822903, 825887397, 837527025, 848612385, 859193865, 19994251455, 20217344325, 102157567401, 103187226801, 312536252003, 315404588903, 9227046511387 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

First column of A027446. - Eric Desbiaux, Mar 29 2013.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A001008(n)*A110566(n). - Arkadiusz Wesolowski, Mar 29 2012

MAPLE

a:= n-> add(1/k, k=1..n)*ilcm($1..n):

seq(a(n), n=1..30);  # Alois P. Heinz, Mar 14 2013

MATHEMATICA

Table[HarmonicNumber[n]*LCM @@ Range[n], {n, 27}] (* Arkadiusz Wesolowski, Mar 29 2012 *)

CROSSREFS

Sequence in context: A001008 A231606 A096617 * A124078 A096795 A160039

Adjacent sequences:  A025526 A025527 A025528 * A025530 A025531 A025532

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

Removed the formulas involving sums of binomials.. they are wrong. sum{k=0..n, sum{j=0..k, binomial(k, j)(-1)^j/(j+1) }} != (1/1 + 1/2 + ... + 1/n) with any offset Stephen Crowley, Jul 11 2009

STATUS

approved

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Last modified July 28 18:22 EDT 2014. Contains 245005 sequences.