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A158947 Inverse Euler transform of A156217. 2
1, 4, 21, 598, 1555, 497652, 299593, 320361028, 1178277701, 357046721884, 67546215517, 19351522090518670, 61054982558011, 1502551437369035044, 33657152197069739919, 45463945109198918808616, 128583032925805678351 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
N. J. A. Sloane, Transforms
FORMULA
a(n) = (1/n)*Sum_{d|n} sigma(d)^d*moebius(n/d).
MAPLE
A158947 := proc(n) add(numtheory[sigma](d)^d*numtheory[mobius](n/d), d=numtheory[divisors](n))/n ; end: seq( A158947(n), n=1..40) ; # R. J. Mathar, Apr 02 2009
# The function EulerInvTransform is defined in A358451.
a := EulerInvTransform(A156217):
seq(a(n), n = 1..17); # Peter Luschny, Nov 21 2022
MATHEMATICA
f[n_] := Block[{d = Divisors@n}, Plus @@ (DivisorSigma[1, d]^d*MoebiusMu[n/d])/n]; Array[f, 17] (* Robert G. Wilson v, May 04 2009 *)
CROSSREFS
Sequence in context: A048164 A118909 A225157 * A000868 A000875 A094046
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Mar 31 2009
EXTENSIONS
Extended by R. J. Mathar, Apr 02 2009
STATUS
approved

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Last modified February 25 05:11 EST 2024. Contains 370310 sequences. (Running on oeis4.)