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 A068316 Run lengths of the Moebius function applied to A051270 (numbers with 5 distinct prime factors). 0
 5, 1, 1, 1, 6, 2, 4, 3, 4, 1, 2, 1, 6, 2, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 2, 2, 2, 1, 3, 2, 2, 1, 2, 1, 3, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 1, 4, 1, 2, 2, 3, 1, 2, 5, 2, 2, 1, 1, 2, 4, 1, 1, 2, 1, 1, 2, 1, 1, 3, 1, 2, 2, 4, 1, 2, 2, 2, 1, 4, 2, 2, 1, 2, 2, 2, 1, 2, 1, 2, 1, 1, 1, 3, 1, 1, 1, 1, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE If we consider A051270 and apply the Moebius function mu(n) to it we get a sequence of values: (-1,-1,-1,-1,-1),0,(-1),0,(-1,-1,-1,-1,-1,-1),0,0,(-1,-1,-1,-1),0,0,0,(-1,-1,-1,-1),0,(-1,-1),0,(-1, ... If we then look at the lengths of runs of equal terms, we get the sequence. If we consider the values of A051270 which are not in A046387 we get numbers which are not squarefree, so mu(A051270(.)) is zero: 4620, 5460, 6930, ... MAPLE runl := 1 : for n from 2 to 1000 do     if numtheory[mobius](A051270(n)) = numtheory[mobius](A051270(n-1)) then         runl := runl+1 ;     else         printf("%d, ", runl) ;         runl := 1;     end if; end do: # R. J. Mathar, Oct 13 2019 CROSSREFS Cf. A046387, A051270. Sequence in context: A102280 A035316 A293718 * A284252 A284254 A309206 Adjacent sequences:  A068313 A068314 A068315 * A068317 A068318 A068319 KEYWORD nonn AUTHOR Jani Melik, Feb 26 2002 EXTENSIONS Corrected and extended by R. J. Mathar, Oct 13 2019 STATUS approved

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Last modified September 30 02:36 EDT 2020. Contains 337432 sequences. (Running on oeis4.)