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A068340 Sum_{k=1..n} mu(k)*k, where mu(k) is the Moebius function. 11
1, -1, -4, -4, -9, -3, -10, -10, -10, 0, -11, -11, -24, -10, 5, 5, -12, -12, -31, -31, -10, 12, -11, -11, -11, 15, 15, 15, -14, -44, -75, -75, -42, -8, 27, 27, -10, 28, 67, 67, 26, -16, -59, -59, -59, -13, -60, -60, -60, -60, -9, -9, -62, -62, -7, -7, 50, 108, 49 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Equals row sums of triangle A143158. - Gary W. Adamson, Jul 27 2008

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

MAPLE

with (numtheory):

a:= proc(n) a(n):= mobius(n)*n +a(n-1) end: a(0):=0:

seq (a(n), n=1..100);  # Alois P. Heinz, Oct 21 2012

MATHEMATICA

Table[Sum[MoebiusMu[k]k, {k, n}], {n, 60}] (* Harvey P. Dale, Feb 01 2012 *)

PROG

(Haskell)

a068340 n = a068340_list !! (n-1)

a068340_list = scanl1 (+) a055615_list

-- Reinhard Zumkeller, Sep 04 2015

CROSSREFS

Cf. A008683, A143158, A055615.

Sequence in context: A115365 A263491 A272427 * A097667 A202388 A283919

Adjacent sequences:  A068337 A068338 A068339 * A068341 A068342 A068343

KEYWORD

sign

AUTHOR

Leroy Quet, Feb 27 2002

STATUS

approved

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Last modified December 12 07:03 EST 2018. Contains 318052 sequences. (Running on oeis4.)