Smallest number x such that phi(x) = phi(x(n)), where x(n) is the n-th arithmetic derivatives of x and x is not equal to x(n).

A246775

Smallest number x such that phi(x) = phi(x(n)), where x(n) is the n-th arithmetic derivatives of x and x is not equal to x(n).

Terms

    a(0) =2a(1) =104a(2) =15a(3) =2565a(4) =4947a(5) =2827a(6) =2834a(7) =153a(8) =3462a(9) =16109a(10) =3201a(11) =7413a(12) =31842a(13) =24541a(14) =66563a(15) =15111a(16) =223995a(17) =542270a(18) =733502a(19) =717874a(20) =521666a(21) =2622290a(22) =2111642a(23) =16169763

External references