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A002819 Liouville's function L(n) = partial sums of A008836.
(Formerly M0042 N0012)
17
0, 1, 0, -1, 0, -1, 0, -1, -2, -1, 0, -1, -2, -3, -2, -1, 0, -1, -2, -3, -4, -3, -2, -3, -2, -1, 0, -1, -2, -3, -4, -5, -6, -5, -4, -3, -2, -3, -2, -1, 0, -1, -2, -3, -4, -5, -4, -5, -6, -5, -6, -5, -6, -7, -6, -5, -4, -3, -2, -3, -2, -3, -2, -3, -2, -1, -2, -3, -4, -3, -4, -5, -6, -7, -6, -7, -8, -7, -8, -9, -10, -9, -8, -9, -8, -7, -6 (list; graph; refs; listen; history; internal format)
OFFSET

0,9

COMMENTS

Short history of conjecture L(n) <= 0 for all n >= 2 by Deborah Tepper Haimo. George Polya conjectured 1919 that L(n) <= 0 for all n >= 2. The conjecture was generally deemed true for nearly 40 years, until 1958, when C. B. Haselgrove proved that L(n) > 0 for infinitely many n. In 1962, R. S. Lehman found that L(906180359) = 1 and in 1980, M. Tanaka discovered that the smallest counterexample of the Polya conjecture occurs when n = 906150257. - Harri Ristiniemi (harri.ristiniemi(AT)nicf.), Jun 23 2001

Prime number theorem is equivalent to a(n)=o(n). - Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 02 2003

REFERENCES

B. Cloitre, A tauberian approach to RH, Arxiv preprint arXiv:1107.0812, 2011

H. Gupta, On a table of values of L(n), Proceedings of the Indian Academy of Sciences. Section A, 12 (1940), 407-409.

H. Gupta, A table of values of Liouville's function L(n), Research Bulletin of East Panjab University, No. 3 (Feb. 1950), 45-55.

D. T. Haimo, Experimentation and Conjecture Are Not Enough, The American Mathematical Monthly Volume 102 Number 2, 1995, page 105.

R. S. Lehman, On Liouville's function, Math. Comp., 14 (1960), 311-320.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

M. Tanaka, A numerical investigation on cumulative sum of the Liouville function, Tokyo J. Math. 3 (1980), 187-189.

LINKS

T. D. Noe, Table of n, a(n) for n = 0..10000

Peter Borwein, Ron Ferguson, and Michael J. Mossinghoff, Sign changes in sums of the Liouville function. Math. Comp. 77 (2008), 1681-1694.

Eric Weisstein's World of Mathematics, Liouville Function

FORMULA

a(n)=determinant of A174856. [From Mats Granvik (mats.granvik(AT)abo.fi), Mar 31 2010]

MAPLE

A002819 := n -> add((-1)^numtheory[bigomega](i), i=1..n): # Peter Luschny, Sep 15 2011

MATHEMATICA

Accumulate[Join[{0}, LiouvilleLambda[Range[90]]]] (* From Harvey P. Dale, Nov 08 2011 *)

PROG

(PARI) a(n)=sum(i=1, n, (-1)^bigomega(i))

(Haskell)

a002819 n = a002819_list !! n

a002819_list = scanl (+) 0 a008836_list

-- Reinhard Zumkeller, Nov 19 2011

CROSSREFS

Cf. A008836, A002053, A028488.

Sequence in context: A106509 A196199 A053615 * A037834 A179765 A004074

Adjacent sequences:  A002816 A002817 A002818 * A002820 A002821 A002822

KEYWORD

nice,sign

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Jul 09 2001

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Last modified February 16 21:45 EST 2012. Contains 205978 sequences.