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A128437 a(n) = floor((numerator of H(n))/n), where H(n) = Sum_{k=1..n} 1/k is the n-th harmonic number. 2
1, 1, 3, 6, 27, 8, 51, 95, 792, 738, 7610, 7168, 88153, 83695, 79717, 152284, 2478954, 793016, 14489252, 2791756, 898002, 867872, 19318117, 56159289, 1362100898, 1322913164, 11575416740, 11264449603, 318174017634, 310156094338 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Numerator of H(n) is a(n)*n + A126083(n).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..2310

EXAMPLE

a(6) = 8 because H(6) = 49/20 and floor(49/6) = 8.

MAPLE

H:=n->sum(1/k, k=1..n): a:=n->floor(numer(H(n))/n): seq(a(n), n=1..35); # Emeric Deutsch, Mar 22 2007

MATHEMATICA

seq = {}; s = 0; Do[s += 1/n; AppendTo[seq, Floor[Numerator[s]/n]], {n, 1, 30}]; seq (* Amiram Eldar, Dec 01 2020 *)

PROG

(PARI) a(n) = numerator(sum(k=1, n, 1/k))\n; \\ Michel Marcus, Feb 01 2019

(Python)

from sympy import harmonic

def A128437(n): return harmonic(n).p//n # Chai Wah Wu, Sep 27 2021

CROSSREFS

Cf. A128438, A001008, A126083.

Sequence in context: A005646 A033194 A304051 * A200654 A208665 A256762

Adjacent sequences:  A128434 A128435 A128436 * A128438 A128439 A128440

KEYWORD

nonn

AUTHOR

Leroy Quet, Mar 03 2007

EXTENSIONS

More terms from Emeric Deutsch, Mar 22 2007

STATUS

approved

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Last modified October 27 19:02 EDT 2021. Contains 348287 sequences. (Running on oeis4.)