A113622 Numbers k such that the reverse of the representation of phi(k) is a substring of k, in base 10.

1, 21, 63, 270, 291, 1065, 2991, 6102, 10087, 10279, 10654, 16528, 144069, 1440069, 10253179, 10657654, 14400069, 16163608, 46676013, 69460293, 2346534651, 2369436474, 6313047393, 10270341004, 10657657654, 14406534069, 23400000651

Offset: 1

Author

Giovanni Resta, Jan 26 2006

Keywords

• base
• nonn

Comments

If p = 480...023 is prime, then k = 3*p = 1440...069 and phi(k) = 960...044, thus k belongs to the sequence.

Examples

			phi(1_440069) = 960044.
		

Crossrefs

Cf. A000010, A069215.

Programs

Mathematica

lst = {}; Do[If[{}!= StringPosition[ToString@n, StringReverse@ToString@EulerPhi@n], AppendTo[lst, n]], {n, 2*10^7}]; lst

Extensions

a(19)-a(27) from Donovan Johnson, May 11 2010