OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1200
EXAMPLE
100th composite is 133; phi(133) = 108 = a(100).
MATHEMATICA
c[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] Table[EulerPhi[c[w], {w, 1, 128}]
With[{nn=100}, EulerPhi[#]&/@Complement[Range[2, nn], Prime[Range[ PrimePi[ nn]]]]] (* Harvey P. Dale, Apr 28 2014 *)
EulerPhi[Select[Range[100], CompositeQ]] (* Harvey P. Dale, Jul 05 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 22 2002
STATUS
approved