A225176 Number of numbers which require n iterations of the bi-unitary totient function (A116550) to reach 1.

1, 1, 1, 2, 3, 2, 2, 4, 7, 6, 13, 12, 16, 24, 31, 51, 66, 87, 126, 139, 187, 260, 331, 412, 551, 693

Offset

1,4

References

M. Lal, H. Wareham and R. Mifflin, Iterates of the bi-unitary totient function, Utilitas Math., 10 (1976), 347-350.

Links

Table of n, a(n) for n=1..26.

Crossrefs

Cf. A116550, A005424, A225175, A225174, A047994, A003271, A225172, A225173.

Sequence in context: A309563 A292588 A335965 * A349271 A349387 A118665

Adjacent sequences: A225173 A225174 A225175 * A225177 A225178 A225179

Keyword

nonn,more

Author

N. J. A. Sloane, May 01 2013

Status

approved