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A347235 Dirichlet convolution of Euler phi with A342001, where A342001(n) = A003415(n) / A003557(n). 8

%I #14 Sep 18 2021 22:02:39

%S 0,1,1,3,1,8,1,7,4,12,1,21,1,16,14,15,1,27,1,33,18,24,1,47,6,28,13,45,

%T 1,87,1,31,26,36,22,69,1,40,30,75,1,119,1,69,51,48,1,99,8,63,38,81,1,

%U 84,30,103,42,60,1,219,1,64,67,63,34,183,1,105,50,183,1,153,1,76,75,117,34,215,1,159,40,84,1,303,42

%N Dirichlet convolution of Euler phi with A342001, where A342001(n) = A003415(n) / A003557(n).

%H Antti Karttunen, <a href="/A347235/b347235.txt">Table of n, a(n) for n = 1..16384</a>

%H Antti Karttunen, <a href="/A347235/a347235.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%F a(n) = Sum_{d|n} A000010(n/d) * A342001(d).

%F a(n) = Sum_{k=1..n} A342001(gcd(n,k)). - _Antti Karttunen_, Sep 02 2021

%o (PARI)

%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

%o A003557(n) = (n/factorback(factorint(n)[, 1]));

%o A342001(n) = (A003415(n) / A003557(n));

%o A347235(n) = sumdiv(n,d,eulerphi(d)*A342001(n/d));

%o (PARI) A347235(n) = sum(k=1,n,A342001(gcd(n,k))); \\ (Slow) - _Antti Karttunen_, Sep 02 2021

%Y Cf. A000010, A003415, A003557, A342001.

%Y Cf. also A346485, A347131, A347233, A347234, A347395.

%K nonn

%O 1,4

%A _Antti Karttunen_, Aug 26 2021

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Last modified August 27 10:11 EDT 2024. Contains 375468 sequences. (Running on oeis4.)