A329153 Sum of the iterated unitary totient function (A047994).

0, 1, 3, 6, 10, 3, 9, 16, 24, 10, 20, 9, 21, 9, 24, 39, 55, 24, 42, 21, 21, 20, 42, 23, 47, 21, 47, 42, 70, 24, 54, 85, 41, 55, 47, 47, 83, 42, 47, 70, 110, 21, 63, 54, 117, 42, 88, 54, 102, 47, 117, 83, 135, 47, 110, 63, 83, 70, 128, 47, 107, 54, 102, 165, 102

Offset

1,3

Comments

Analogous to A092693 with the unitary totient function uphi instead of the Euler totient function phi (A000010).

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Formula

a(n) = n for n in A286067.

Example

a(4) = uphi(4) + uphi(uphi(4)) + uphi(uphi(uphi(4))) = 3 + 2 + 1 = 6.

Mathematica

uphi[1] = 1; uphi[n_] := Times @@ (-1 + Power @@@ FactorInteger[n]); Table[Plus @@ FixedPointList[uphi, n] - n - 1, {n, 1, 100}]

Crossrefs

Cf. A003271, A047994, A049865, A092693, A225172, A225173, A286067.

Sequence in context: A330376 A120028 A333611 * A337771 A232175 A065234

Adjacent sequences: A329150 A329151 A329152 * A329154 A329155 A329156

Keyword

nonn

Author

Amiram Eldar, Feb 25 2020

Status

approved