A090557 a(n) = phi(A090556(n)).

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

Offset: 1

Author

Amarnath Murthy, Dec 10 2003

Keywords

• nonn

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

Crossrefs

Cf. A014573, A090556.

Programs

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 *)

Extensions

More terms from David Wasserman, Jan 04 2006

Missing term a(1) prepended by Ivan Neretin, May 01 2016