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 A172354 n such that the Moebius function take successively, from n, the values -1,0,-1,0,-1,0. 3
 195, 1491, 1547, 1947, 2139, 2715, 2749, 2751, 2847, 2967, 3359, 3615, 3819, 4011, 4013, 4015, 4047, 4155, 4547, 5019, 5449, 5647, 5741, 5779, 6351, 6353, 6355, 6447, 6547, 6563, 6565, 6567, 6947, 6959, 6961, 6963, 7347, 7503, 7545, 7683, 8007, 9339, 10091 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 826. G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 5th ed., Oxford Univ. Press, 1979, th. 262 and 287. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 Marc Deléglise and Joël Rivat, Computing the summation of the Mobius function, Experiment. Math. 5:4 (1996), pp. 291-295. Ed Pegg Jr., The Mobius function (and squarefree numbers) Primefan, Mobius and Mertens Values For n=1 to 2500 G. Villemin's Almanac of Numbers, Nombres de Moebius et de Mertens MAPLE with(numtheory): for n from 1 to 15000 do; if mobius(n)= -1 and mobius(n+1) = 0 and mobius(n+2)= -1 and mobius(n+3)= 0 and mobius(n+4)= -1 and mobius(n+5) = 0 then print(n); else fi ; od; MATHEMATICA SequencePosition[MoebiusMu[Range[11000]], {-1, 0, -1, 0, -1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 17 2016 *) PROG (PARI) is(n)=moebius(n)<0 && !moebius(n+1) && moebius(n+2)<0 && !moebius(n+3) && moebius(n+4)<0 && !moebius(n+5) \\ Charles R Greathouse IV, Sep 26 2013 CROSSREFS Moebius (or Möbius) function mu(n): A008683, A007423, A002321, A002996. Sequence in context: A157239 A158003 A225713 * A295130 A257765 A259694 Adjacent sequences:  A172351 A172352 A172353 * A172355 A172356 A172357 KEYWORD nonn AUTHOR Michel Lagneau, Feb 01 2010 EXTENSIONS a(4) inserted by Charles R Greathouse IV, Sep 26 2013 STATUS approved

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Last modified June 17 05:39 EDT 2021. Contains 345080 sequences. (Running on oeis4.)