Numbers k of the form k = ab (the decimal concatenation of a and b) such that phi(ab) = a*b + 1.

A336191

Numbers k of the form k = ab (the decimal concatenation of a and b) such that phi(ab) = a*b + 1.

Terms

    a(0) =57a(1) =195a(2) =319a(3) =5595a(4) =11709a(5) =77097a(6) =114765a(7) =1313667a(8) =1348559a(9) =4752465a(10) =10219099a(11) =11031119a(12) =185573199a(13) =2918945715a(14) =3165616929a(15) =12233666703a(16) =16996664613a(17) =18052811909a(18) =20650199699a(19) =38081370319a(20) =58943659521a(21) =195823876095a(22) =236323024041a(23) =242687655369a(24) =342764528277a(25) =677924155713

External references