|
| |
|
|
A062401
|
|
Phi(sigma(n)).
|
|
33
|
|
|
|
1, 2, 2, 6, 2, 4, 4, 8, 12, 6, 4, 12, 6, 8, 8, 30, 6, 24, 8, 12, 16, 12, 8, 16, 30, 12, 16, 24, 8, 24, 16, 36, 16, 18, 16, 72, 18, 16, 24, 24, 12, 32, 20, 24, 24, 24, 16, 60, 36, 60, 24, 42, 18, 32, 24, 32, 32, 24, 16, 48, 30, 32, 48, 126, 24, 48, 32, 36, 32, 48, 24, 96, 36, 36, 60
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, p. 14.
|
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..10000
|
|
|
FORMULA
|
sigma[a(x)]=A062402(sigma[x]) or phi[A062402(x)]=a(phi[x]). - Labos E. (labos(AT)ana.sote.hu), Jul 22 2004
|
|
|
EXAMPLE
|
a(9)=12 because sigma(9)=13 and phi(13)= 12.
|
|
|
MATHEMATICA
|
Table[EulerPhi[DivisorSigma[1, n]], {n, 1, 80}] (* Carl Najafi, Aug 16 2011 *)
|
|
|
PROG
|
(PARI) j(e)=eulerphi(sigma(n)); vector(150, n, j(e))
(PARI) { for (n=1, 10000, write("b062401.txt", n, " ", eulerphi(sigma(n))) ) } [From Harry J. Smith, Aug 07 2009]
(Haskell)
a062401 = a000010 . a000203 -- Reinhard Zumkeller, Jan 04 2013
|
|
|
CROSSREFS
|
Cf. A000203, A000010, A062402.
Cf. A096852, A096857, A096994, A096995.
Cf. A033632.
Sequence in context: A068976 A124859 A021446 * A138949 A138951 A163370
Adjacent sequences: A062398 A062399 A062400 * A062402 A062403 A062404
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Jason Earls (zevi_35711(AT)yahoo.com), Jul 08 2001
|
|
|
STATUS
|
approved
|
| |
|
|
