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A025529 a(n) = (1/1 + 1/2 + ... + 1/n)*LCM{1,2,...,n}. 15
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.

REFERENCES

Haight, Frank A., and Robert B. Jones. "A probabilistic treatment of qualitative data with special reference to word association tests." Journal of Mathematical Psychology 11.3 (1974): 237-244. [Denominators of fractions in Eq. 21.]

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

Differs from A096617 at 7th term.

Cf. A001008, A027446, A110566.

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 December 9 21:41 EST 2016. Contains 278987 sequences.