cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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

Original entry on oeis.org

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

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Author

Amarnath Murthy, Dec 10 2003

Keywords

Comments

Starting at n=9, all known terms are of the form 3*2^k. - Ivan Neretin, May 01 2016

Crossrefs

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
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