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A144654 Numerator of Sum_{k=1..n} k*H_{n+k} where H_m = Sum_{i=1..m}. 2
0, 3, 6, 14, 155, 167, 1239, 433, 8109, 8389, 95051, 97571, 1298453, 1326173, 1351913, 1375937, 47547623, 48268343, 930031437, 314094559, 317974435, 64333911, 498634963, 1511424393, 38157431275, 38514379867, 349718397003, 352692968603, 10311277859587 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Muniru A Asiru, Table of n, a(n) for n = 0..1000

EXAMPLE

0, 3/2, 6, 14, 155/6, 167/4, 1239/20, 433/5, 8109/70, 8389/56, ...

MAPLE

a:=n->add(k*add(1/i, i=1..n+k), k=1..n): seq(numer(a(n)), n=0..30); # Muniru A Asiru, Dec 03 2018

MATHEMATICA

a[n_] := Numerator[Sum[k * HarmonicNumber[n+k], {k, 1, n}]]; Array[a, 30, 0] (* Amiram Eldar, Dec 03 2018 *)

PROG

(PARI) a(n) = numerator(sum(k=1, n, k*sum(i=1, n+k, 1/i))); \\ Michel Marcus, Dec 03 2018

(GAP) List(List([0..30], n->Sum([1..n], k->k*Sum([1..n+k], i->1/i))), NumeratorRat); # Muniru A Asiru, Dec 03 2018

CROSSREFS

Suggested by A102720/A144653.

Cf. A001008, A002805, A144655.

Sequence in context: A129090 A324222 A058141 * A132279 A066107 A162276

Adjacent sequences:  A144651 A144652 A144653 * A144655 A144656 A144657

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, Jan 28 2009

STATUS

approved

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Last modified April 9 14:04 EDT 2020. Contains 333353 sequences. (Running on oeis4.)