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A117291
a(n) = phi(n)^(n-phi(n))
1
1, 1, 2, 4, 4, 16, 6, 256, 216, 4096, 10, 65536, 12, 1679616, 2097152, 16777216, 16, 2176782336, 18, 68719476736, 5159780352, 1000000000000, 22, 281474976710656, 3200000, 1283918464548864, 198359290368, 184884258895036416, 28
OFFSET
1,3
LINKS
EXAMPLE
a(9) = phi(9)^(9-phi(9)) = 6^3 = 216
MATHEMATICA
ep[n_]:=Module[{p=EulerPhi[n]}, p^(n-p)]; Array[ep, 30] (* Harvey P. Dale, Mar 25 2014 *)
PROG
(PARI) a(n) = eulerphi(n)^(n-eulerphi(n)) \\ Michel Marcus, Jun 01 2013
CROSSREFS
Sequence in context: A218075 A366709 A064449 * A246047 A079102 A071337
KEYWORD
nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 23 2006
EXTENSIONS
Corrected by Michel Marcus, Jun 01 2013
STATUS
approved