|
0, 1, 0, 2, -2, 4, -2, 2, -2, 6, -6, 8, -6, 2, 0, 8, -10, 12, -10, 4, -2, 12, -14, 12, -8, 6, -6, 16, -20, 22, -14, 4, -4, 8, -12, 24, -18, 6, -8, 24, -28, 30, -22, 4, -2, 24, -30, 26, -22, 12, -8, 28, -34, 22, -16, 12, -8, 30, -42, 44, -30, 6, -4, 16, -28, 46, -34, 12, -20, 46, -46, 48, -36, 4
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,4
|
|
LINKS
|
|
|
FORMULA
|
G.f.: -1 + (1 - x)*Sum_{k>=1} mu(k)*x^(k-1)/(1 - x^k)^2. - Ilya Gutkovskiy, Jan 29 2017
|
|
MAPLE
|
numtheory[phi](n+1)-numtheory[phi](n) ;
end proc:
|
|
MATHEMATICA
|
|
|
PROG
|
(Magma) [(EulerPhi(n+1) - EulerPhi(n)): n in [1..100]]; // Vincenzo Librandi, Sep 30 2013
(PARI) a(n) = eulerphi(n+1) - eulerphi(n); \\ Michel Marcus, Jan 29 2017
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|
CROSSREFS
|
|
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KEYWORD
|
sign
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|