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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
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
Sequence in context: A265529 A292597 A101656 * A230875 A035660 A302405
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 March 19 01:57 EDT 2024. Contains 370952 sequences. (Running on oeis4.)