A362486 Infinitary nontotient numbers: values not in the range of the infinitary totient function iphi (A091732).

5, 7, 9, 11, 13, 14, 17, 19, 21, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 47, 49, 50, 51, 53, 55, 57, 59, 61, 62, 63, 65, 67, 68, 69, 71, 73, 74, 75, 76, 77, 79, 81, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 98, 99, 101, 103, 105, 107, 109, 110, 111

Offset

1,1

Comments

Numbers k such that A091732(x) = k has no solution, i.e., A362485(k) = 0.

Most of the odd numbers are in this sequence. Odd numbers that are not here are 1, 3, 15, 45, 255, 765, 3825, 11475, 65535, 196605, 983025, ..., which are the values of iphi at powers of 2.

Links

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

Formula

A362485(a(n)) = 0.

Mathematica

Select[Range[120], Length[invIPhi[#]] == 0 &] (* using the function invIPhi from A362484 *)

Crossrefs

Cf. A091732, A362484, A362485.

Similar sequences: A005277, A005278, A347771, A362182.

Sequence in context: A325797 A128163 A177088 * A168146 A343064 A106505

Adjacent sequences: A362483 A362484 A362485 * A362487 A362488 A362489

Keyword

nonn

Author

Amiram Eldar, Apr 22 2023

Status

approved