A344210 - OEIS

A344210

a(n) = Sum_{d|n} mu(n/d) * d^n / phi(n).

1, 3, 13, 120, 781, 22932, 137257, 4177920, 64566801, 2497558338, 28531167061, 2228476723200, 25239592216021, 1851888100411464, 54736732481116543, 2305807824841605120, 51702516367896047761, 6557709646516945221396, 109912203092239643840221

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..19.

FORMULA

a(n) = J_n(n) / phi(n) = A067858(n) / A000010(n).

MATHEMATICA

Table[DivisorSum[n, MoebiusMu[n/#]*#^n/EulerPhi[n]&], {n, 20}] (* Giorgos Kalogeropoulos, May 13 2021 *)

PROG

(PARI) a(n) = sumdiv(n, d, moebius(n/d)*d^n)/eulerphi(n);

CROSSREFS

Main diagonal of A263950.

Cf. A000010, A067858.

Sequence in context: A262147 A364327 A057865 * A260847 A121921 A191955

Adjacent sequences: A344207 A344208 A344209 * A344211 A344212 A344213

KEYWORD

nonn

AUTHOR

Seiichi Manyama, May 12 2021

STATUS

approved