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 A053865 A third order generalization of the Mobius function of n. 3
 1, 1, 1, 1, 1, 1, 1, -1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Compares the exponents of the factors of the canonical prime factorization of n with 3 as detailed in A053864. LINKS R. J. Mathar, Table of n, a(n) for n = 1..1000 MATHEMATICA a[n_] := Which[ee = FactorInteger[n][[All, 2]]; AnyTrue[ee, # > 3 &], 0, AnyTrue[ee, # < 3 &], 1, True, (-1)^Length[ee]]; Array[a, 100] (* Jean-François Alcover, Feb 09 2018 *) CROSSREFS Cf. A008683, A053864, A053981. Sequence in context: A133011 A167850 A167851 * A166234 A074481 A015420 Adjacent sequences:  A053862 A053863 A053864 * A053866 A053867 A053868 KEYWORD sign AUTHOR N. J. A. Sloane, Apr 08 2000 STATUS approved

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Last modified September 22 20:30 EDT 2018. Contains 315270 sequences. (Running on oeis4.)