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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
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
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: A339413 A114144 A050820 * A279697 A133179 A282221
KEYWORD
sign
AUTHOR
Reinhard Zumkeller, Sep 04 2015
STATUS
approved