This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A276040 Least k such that n^n divides phi(k^k) (k > 0). 1
 1, 4, 6, 8, 10, 12, 14, 12, 18, 20, 22, 24, 26, 28, 30, 24, 34, 36, 38, 40, 42, 44, 46, 36, 50, 52, 45, 56, 58, 60, 62, 48, 66, 68, 70, 72, 74, 76, 78, 60, 82, 84, 86, 88, 90, 92, 94, 72, 98, 100, 102, 104, 106, 90, 110, 84, 114, 116, 118, 120 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Indices of odd terms in this sequence are 1, 27, 81, 135, 189, 297, 343, 351, 405, 459, 513, 621, 625, 675, 783, ... LINKS EXAMPLE a(3) = 6 because 3^3 divides phi(6^6) = 15552. MATHEMATICA Table[k = 1; While[! Divisible[EulerPhi[k^k], n^n], k++]; k, {n, 60}] (* Michael De Vlieger, Aug 21 2016 *) PROG (PARI) a(n) = {my(k = 1); while(eulerphi(k^k) % n^n, k++); k; } CROSSREFS Cf. A064447. Sequence in context: A063287 A228358 A134331 * A090334 A272601 A322368 Adjacent sequences:  A276037 A276038 A276039 * A276041 A276042 A276043 KEYWORD nonn AUTHOR Altug Alkan, Aug 17 2016 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 20 17:54 EDT 2019. Contains 322310 sequences. (Running on oeis4.)