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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.
2
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
OFFSET
1,2
COMMENTS
This is a subsequence of A115921, which in turn is a subsequence of A082060. - M. F. Hasler, Nov 28 2007
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
KEYWORD
base,nonn
AUTHOR
Giovanni Resta, Jan 26 2006
EXTENSIONS
a(24)-a(30) from Donovan Johnson, Aug 27 2010
STATUS
approved