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 A090557 a(n) = phi(A090556(n)). 2
 1, 1, 2, 2, 4, 4, 4, 4, 12, 12, 12, 12, 24, 24, 24, 24, 24, 48, 96, 96, 96, 192, 192, 192, 192, 192, 192, 192, 192, 192, 192, 384, 384, 384, 384, 384, 768, 768, 768, 768, 768, 768, 768, 1536, 1536, 1536, 1536, 1536, 1536, 1536, 1536, 3072, 3072, 3072, 3072, 3072 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Starting at n=9, all known terms are of the form 3*2^k. - Ivan Neretin, May 01 2016 LINKS Ivan Neretin, Table of n, a(n) for n = 1..308 MATHEMATICA EulerPhi@ NestList[Function[n, SelectFirst[Range[n + 1, 10^4], Divisible[EulerPhi@ #, EulerPhi@ n] &]], 1, 55] (* Michael De Vlieger, May 01 2016, Version 10 *) CROSSREFS Cf. A014573, A090556. Sequence in context: A265529 A292597 A101656 * A230875 A035660 A302405 Adjacent sequences:  A090554 A090555 A090556 * A090558 A090559 A090560 KEYWORD nonn AUTHOR Amarnath Murthy, Dec 10 2003 EXTENSIONS More terms from David Wasserman, Jan 04 2006 Missing term a(1) prepended by Ivan Neretin, May 01 2016 STATUS approved

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Last modified February 20 04:12 EST 2020. Contains 332063 sequences. (Running on oeis4.)