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 A049115 Repeatedly apply Euler phi to n; a(n) = number of iterations that are applied to numbers that are not powers of 2. 2
 0, 0, 1, 0, 1, 1, 2, 0, 2, 1, 2, 1, 2, 2, 1, 0, 1, 2, 3, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 1, 2, 0, 2, 1, 2, 2, 3, 3, 2, 1, 2, 2, 3, 2, 2, 3, 4, 1, 3, 2, 1, 2, 3, 3, 2, 2, 3, 3, 4, 1, 2, 2, 3, 0, 2, 2, 3, 1, 3, 2, 3, 2, 3, 3, 2, 3, 2, 2, 3, 1, 4, 2, 3, 2, 1, 3, 3, 2, 3, 2, 3, 3, 2, 4, 3, 1, 2, 3, 2, 2, 3, 1, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 LINKS T. D. Noe, Table of n, a(n) for n=1..10000 FORMULA The smallest x so that Nest[ EulerPhi, n, x ] = 2^w is just achieved. EXAMPLE If n is a power of 2, then a(n)=0 by definition. If n=59049, then {59049,39366,13122,4374,1458,486,54,18,6,2,1}. This phi-sequence has a length of 12 and includes 10 non-2-powers, so a(59049)=8. CROSSREFS Sequence in context: A039701 A025822 A051585 * A029367 A192541 A099302 Adjacent sequences:  A049112 A049113 A049114 * A049116 A049117 A049118 KEYWORD nonn AUTHOR Labos E. (labos(AT)ana.sote.hu) STATUS approved

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