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 A060605 a(n) = sum of lengths of the iteration sequences of Euler totient function from 1 to n. 0
 1, 3, 6, 9, 13, 16, 20, 24, 28, 32, 37, 41, 46, 50, 55, 60, 66, 70, 75, 80, 85, 90, 96, 101, 107, 112, 117, 122, 128, 133, 139, 145, 151, 157, 163, 168, 174, 179, 185, 191, 198, 203, 209, 215, 221, 227, 234, 240, 246, 252, 259, 265, 272, 277, 284, 290, 296, 302 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Partial sums of A049108. - Joerg Arndt, Jan 06 2015 LINKS Paul Erdős, Andrew Granville, Carl Pomerance and Claudia Spiro, On the normal behavior of the iterates of some arithmetic functions, Analytic number theory, Birkhäuser Boston, 1990, pp. 165-204. Paul Erdos, Andrew Granville, Carl Pomerance and Claudia Spiro, On the normal behavior of the iterates of some arithmetic functions, Analytic number theory, Birkhäuser Boston, 1990, pp. 165-204. [Annotated copy with A-numbers] Harold Shapiro, An arithmetic function arising from the phi function, Amer. Math. Monthly, Vol. 50, No. 1 (1943), 18-30. FORMULA a(n) = sum( j=1..n, A049108(j) ). EXAMPLE Iteration sequences of Phi applied to 1, 2, 3, 4, 5, 6 give lengths 1, 2, 3, 3, 4, 3 with partial sums as follows:1, 3, 5, 9, 13, 16 resulting in first...6th terms here. PROG (PARI) a049108(n)=my(t=1); while(n>1, t++; n=eulerphi(n)); t; vector(80, n, sum(j=1, n, a049108(j))) \\ Michel Marcus, Jan 06 2015 CROSSREFS Cf. A049108, A003434. Sequence in context: A066343 A184909 A289037 * A278449 A006590 A061781 Adjacent sequences:  A060602 A060603 A060604 * A060606 A060607 A060608 KEYWORD nonn AUTHOR Labos Elemer, Apr 13 2001 STATUS approved

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Last modified February 22 19:59 EST 2019. Contains 320403 sequences. (Running on oeis4.)