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A104194
a(n) = phi(n) - lambda(n).
2
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
1,8
LINKS
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
MATHEMATICA
Table[EulerPhi[n] - CarmichaelLambda[n], {n, 1, 200}]
PROG
(PARI) a(n) = eulerphi(n) - lcm(znstar(n)[2]); \\ Michel Marcus, Mar 18 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Mar 12 2005
STATUS
approved