A333611 Sum of the iterated infinitary totient function iphi (A091732).

0, 1, 3, 6, 10, 3, 9, 6, 14, 10, 20, 9, 21, 9, 14, 29, 45, 14, 32, 21, 21, 20, 42, 9, 33, 21, 45, 32, 60, 14, 44, 29, 41, 45, 33, 33, 69, 32, 33, 21, 61, 21, 63, 44, 61, 42, 88, 44, 92, 33, 61, 69, 121, 45, 61, 32, 69, 60, 118, 33, 93, 44, 92, 106, 92, 41, 107

Offset

1,3

Links

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

Example

a(3) = iphi(3) + iphi(iphi(3)) = 2 + 1 = 3.

Mathematica

f[p_, e_] := p^(2^(-1 + Position[Reverse @ IntegerDigits[e, 2], 1])); iphi[1] = 1; iphi[n_] := Times @@ (Flatten@(f @@@ FactorInteger[n]) - 1); a[n_] := Plus @@ NestWhileList[iphi, n, # != 1 &] - n; Array[a, 100]

Crossrefs

Cf. A091732, A092693, A329153, A330273, A331273, A333609.

Sequence in context: A194049 A330376 A120028 * A329153 A337771 A232175

Adjacent sequences: A333608 A333609 A333610 * A333612 A333613 A333614

Keyword

nonn

Author

Amiram Eldar, Mar 28 2020

Status

approved