A137598 Numbers n such that phi(n)=reversal(n)+1.

1541, 13811, 30590, 57871382, 95793434, 99178725, 3664133243, 7699397795, 1992945982991, 7028723775455

Offset

1,1

Comments

a(11) > 10^13. - Giovanni Resta, Aug 12 2019

Links

Table of n, a(n) for n=1..10.

Example

phi(95793434)=43439760=43439759+1=reversal(95793434)+1, so 95793434 is in the sequence.

Mathematica

Do[If[EulerPhi@n==FromDigits@Reverse@IntegerDigits@n+1, Print[n]], {n, 255000000}]

Prog

(PARI) isok(m) = eulerphi(m) == fromdigits(Vecrev(digits(m)))+1; \\ Michel Marcus, Aug 13 2019

Crossrefs

Cf. A000010, A004086, A130000, A137599.

Sequence in context: A092717 A203134 A083734 * A252966 A133560 A232102

Adjacent sequences: A137595 A137596 A137597 * A137599 A137600 A137601

Keyword

nonn,base,more

Author

Farideh Firoozbakht, Feb 23 2008

Extensions

a(6)-a(8) from Giovanni Resta, Oct 28 2012

a(9)-a(10) from Giovanni Resta, Aug 12 2019

Status

approved