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 A111409 f(f(n+1))-f(f(n)), where f(0)=0, and for m>0, f(m) = phi(m) = A000010(m). 0
 1, 0, 0, 0, 1, -1, 1, 0, 0, 0, 2, -2, 2, -2, 2, 0, 4, -6, 4, -2, 0, 0, 6, -6, 4, -4, 2, -2, 8, -8, 4, 0, 0, 0, 0, -4, 8, -6, 2, 0, 8, -12, 8, -4, 0, 2, 12, -14, 4, -4, 8, -8, 16, -18, 10, -8, 4, 0, 16, -20, 8, -8, 4, 4, 0, -8, 12, -4, 4, -12, 16, -16, 16, -12, 4, -4, 4, -8, 16, -8, 2, -2, 24, -32, 24, -20, 12, -8, 24, -32, 16, -4, -4, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,11 LINKS CROSSREFS Sequence in context: A137934 A133738 A240713 * A125088 A226456 A343642 Adjacent sequences:  A111406 A111407 A111408 * A111410 A111411 A111412 KEYWORD sign AUTHOR N. J. A. Sloane, Nov 12 2005 EXTENSIONS Definition corrected by N. J. A. Sloane, Feb 14 2018 STATUS approved

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Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)