A124219 a(n)= m-th positive divisor of n, where phi(n) is number of positive integers which are <= n and are coprime to n, d(n) is the number of positive divisors of n and m = d(n) if d(n)|phi(n), else m = phi(n) mod d(n).

1, 1, 3, 2, 5, 2, 7, 8, 9, 10, 11, 4, 13, 2, 15, 4, 17, 18, 19, 2, 21, 2, 23, 24, 5, 26, 3, 28, 29, 30, 31, 8, 33, 34, 35, 3, 37, 2, 39, 40, 41, 6, 43, 2, 45, 2, 47, 8, 49, 2, 51, 52, 53, 2, 55, 56, 57, 58, 59, 4, 61, 2, 63, 8, 65, 6, 67, 2, 69, 70, 71, 72, 73, 74, 15, 76, 77, 78, 79, 2

Offset: 1

Author

Leroy Quet, Oct 19 2006

Keywords

• nonn

Crossrefs

Cf. A000005, A000010, A124218, A124331.

Programs

Mathematica

f[n_] := Block[{d = Divisors[n]}, d[[Mod[EulerPhi[n], Length[d], 1]]]];Table[f[n], {n, 90}] (* Ray Chandler, Oct 26 2006 *)

Extensions

Edited and extended by Ray Chandler, Oct 26 2006