

A230028


Numbers n such that phi(n) = reversal(n20).


1




OFFSET

1,1


COMMENTS

If p=10^m+3 is prime then 8*p is in the sequence.
84803024 is the only known term of the sequence which is not of this form.
a(7) > 10^11.  Giovanni Resta, Dec 13 2013


LINKS

Table of n, a(n) for n=1..6.


EXAMPLE

phi(104)=48=reversal(84)=reversal(10420).


MATHEMATICA

Do[If[EulerPhi[n]==FromDigits[Reverse[IntegerDigits[n20]]], Print[n]], {n, 21, 90000000}]


CROSSREFS

Cf. A000010, A004086.
Sequence in context: A206021 A206014 A106298 * A132434 A187589 A200196
Adjacent sequences: A230025 A230026 A230027 * A230029 A230030 A230031


KEYWORD

nonn,base,bref,more


AUTHOR

Farideh Firoozbakht, Dec 13 2013


EXTENSIONS

a(6) from Giovanni Resta, Dec 13 2013


STATUS

approved



