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Dirichlet convolution of Kimberling's paraphrases (A003602) with tau (number of divisors, A000005).
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%I #12 Nov 21 2021 10:17:07

%S 1,3,4,6,5,12,6,10,12,15,8,24,9,18,22,15,11,36,12,30,27,24,14,40,22,

%T 27,34,36,17,66,18,21,37,33,36,72,21,36,42,50,23,81,24,48,72,42,26,60,

%U 36,66,52,54,29,102,50,60,57,51,32,132,33,54,90,28,57,111,36,66,67,108,38,120,39,63,104,72,63,126,42,75

%N Dirichlet convolution of Kimberling's paraphrases (A003602) with tau (number of divisors, A000005).

%H Antti Karttunen, <a href="/A349372/b349372.txt">Table of n, a(n) for n = 1..20000</a>

%F a(n) = Sum_{d|n} A003602(n/d) * A000005(d).

%t k[n_] := (n / 2^IntegerExponent[n, 2] + 1)/2; a[n_] := DivisorSum[n, k[#] * DivisorSigma[0, n/#] &]; Array[a, 100] (* _Amiram Eldar_, Nov 16 2021 *)

%o (PARI)

%o A003602(n) = (1+(n>>valuation(n,2)))/2;

%o A349372(n) = sumdiv(n,d,A003602(n/d)*numdiv(d));

%Y Cf. A000005, A003602.

%Y Cf. A347954, A347955, A347956, A349136, A349370, A349371, A349373, A349374, A349375, A349390, A349431, A349444, A349447 for Dirichlet convolutions of other sequences with A003602.

%Y Cf. also A349392.

%K nonn

%O 1,2

%A _Antti Karttunen_, Nov 15 2021