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 A072073 Number of solutions to Cototient(x)=A051953[x]= 2^n. 0
 1, 2, 3, 3, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE InvCototient[2^0] has infinite number of entries, so 2^0=1 is left out. n=14: 2^14=16384, InvCototient[16384]= {24576,28672,31744,32512,32764,32768}, so a(14)=6; a(n) increases at A000043(n). CROSSREFS Cf. A051953, A058764, A000043, A063740. Sequence in context: A256544 A321211 A130500 * A320757 A061716 A126236 Adjacent sequences:  A072070 A072071 A072072 * A072074 A072075 A072076 KEYWORD nonn AUTHOR Labos Elemer, Jun 13 2002 STATUS approved

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)