A113781 - OEIS

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A113781

Numbers k such that the representation of phi(k) is a cyclic permutation of that of k, in base 10.

1, 21, 63, 502, 4435, 5229, 5637, 6822, 8022, 35683, 98802, 176481, 210526, 421052, 442881, 480249, 529443, 544435, 640170, 842104, 920262, 976482, 7390422, 21251221, 28934019, 36174255, 36563587, 51804709, 59963997, 60550457

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OFFSET

1,2

COMMENTS

This is a subsequence of A115921, which in turn is a subsequence of A082060. - M. F. Hasler, Nov 28 2007

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

phi(442881) = 288144.

MATHEMATICA

lst = {}; Do[s = ToString@n; d = ToString@EulerPhi@n; If[StringLength@d == StringLength@n && {}!= StringPosition[s<>s, d], AppendTo[lst, n]], {n, 10^6}]; lst

lst = {}; Do[s = ToString(AT)n; d = ToString(AT)EulerPhi(AT)n; If[StringLength(AT)d == StringLength(AT)n && {}!= StringPosition[s<>s, d], AppendTo[lst, n]], {n, 10^6}]; lst (* M. F. Hasler, Nov 28 2007 *)

CROSSREFS

Cf. A000010, A115921, A082060.

Sequence in context: A115921 A251808 A072395 * A299450 A300088 A033481

Adjacent sequences: A113778 A113779 A113780 * A113782 A113783 A113784

KEYWORD

base,nonn

AUTHOR

Giovanni Resta, Jan 26 2006

EXTENSIONS

a(24)-a(30) from Donovan Johnson, Aug 27 2010

STATUS

approved