|
Search: id:A086831
|
|
| |
|
| 1, 1, -1, -2, -1, -1, -1, 0, 0, -1, -1, 2, -1, -1, 1, 0, -1, 0, -1, 2, 1, -1, -1, 0, 0, -1, 0, 2, -1, 1, -1, 0, 1, -1, 1, 0, -1, -1, 1, 0, -1, 1, -1, 2, 0, -1, -1, 0, 0, 0, 1, 2, -1, 0, 1, 0, 1, -1, -1, -2, -1, -1, 0, 0, 1, 1, -1, 2, 1, 1, -1, 0, -1, -1, 0, 2, 1, 1, -1, 0, 0, -1, -1, -2, 1, -1, 1, 0, -1, 0, 1, 2, 1, -1, 1, 0, -1, 0, 0, 0, -1, 1, -1, 0, -1
(list; graph; listen)
|
|
|
OFFSET
|
1,4
|
|
|
REFERENCES
|
T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976.
|
|
FORMULA
|
For general k >= 1 c_k(n) = phi(n)*mu(n/gcd(n, k)) / phi(n/gcd(n, k)) so c_1(n) = mu(n) (A008683(n)).
a(n) = phi(n)*mu(n/gcd(n, 2)) / phi(n/gcd(n, 2))
|
|
MAPLE
|
with(numtheory):a:=n->phi(n)*mobius(n/gcd(n, 2))/phi(n/gcd(n, 2)): seq(a(n), n=1..130); (Deutsch)
|
|
CROSSREFS
|
Cf. A000010, A008683, A054532, A054533, A054534, A054535.
Sequence in context: A134022 A085975 A005091 this_sequence A111405 A089053 A068462
Adjacent sequences: A086828 A086829 A086830 this_sequence A086832 A086833 A086834
|
|
KEYWORD
|
sign,easy,mult
|
|
AUTHOR
|
Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 07 2003
|
|
EXTENSIONS
|
Corrected and extended by Emeric Deutsch (deutsch(AT)duke.poly.edu), Dec 23 2004
|
|
|
Search completed in 0.002 seconds
|
