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A261869 First differences of A055615. 4
-3, -1, 3, -5, 11, -13, 7, 0, 10, -21, 11, -13, 27, 1, -15, -17, 17, -19, 19, 21, 1, -45, 23, 0, 26, -26, 0, -29, -1, -1, 31, 33, 1, 1, -35, -37, 75, 1, -39, -41, -1, -1, 43, 0, 46, -93, 47, 0, 0, 51, -51, -53, 53, 55, -55, 57, 1, -117, 59, -61, 123, -62, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = (n+1)*mu(n+1) - n*mu(n), where mu = A008683 (Moebius function);

a(A068781(n)) = 0;

abs(a(n)) <= 2*n + 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

#[[2]]-#[[1]]&/@Partition[Table[n*MoebiusMu[n], {n, 70}], 2, 1] (* Harvey P. Dale, Apr 17 2016 *)

PROG

(Haskell)

import Data.List (genericIndex)

a261869 n = genericIndex a261869_list (n - 1)

a261869_list = zipWith (-) (tail a055615_list) a055615_list

CROSSREFS

Cf. A008683, A055615, A068781, A261890 (first differences).

Sequence in context: A234587 A114144 A050820 * A279697 A133179 A282221

Adjacent sequences:  A261866 A261867 A261868 * A261870 A261871 A261872

KEYWORD

sign

AUTHOR

Reinhard Zumkeller, Sep 04 2015

STATUS

approved

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Last modified July 5 19:02 EDT 2020. Contains 335473 sequences. (Running on oeis4.)