A104194 a(n) = phi(n) - lambda(n).

0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 4, 4, 0, 0, 0, 4, 6, 0, 0, 6, 0, 0, 0, 6, 0, 4, 0, 8, 10, 0, 12, 6, 0, 0, 12, 12, 0, 6, 0, 10, 12, 0, 0, 12, 0, 0, 16, 12, 0, 0, 20, 18, 18, 0, 0, 12, 0, 0, 30, 16, 36, 10, 0, 16, 22, 12, 0, 18, 0, 0, 20, 18, 30, 12, 0, 28, 0, 0, 0, 18, 48, 0, 28, 30, 0, 12

Offset: 1

Author

Roger L. Bagula, Mar 12 2005

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000010, A002322, A033948, A034380.

Programs

Mathematica

Table[EulerPhi[n] - CarmichaelLambda[n], {n, 1, 200}]

PARI

a(n) = eulerphi(n) - lcm(znstar(n)[2]); \\ Michel Marcus, Mar 18 2016

Formula

a(n) = A000010(n) - A002322(n). - Michel Marcus, Mar 18 2016

a(n) = 0 if and only if n is in A033948. - Amiram Eldar, Nov 16 2024