The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A349431 Dirichlet convolution of A003602 (Kimberling's paraphrases) with A055615 (Dirichlet inverse of n) 14

%I #17 Nov 21 2021 01:18:22

%S 1,-1,-1,-1,-2,1,-3,-1,-1,2,-5,1,-6,3,4,-1,-8,1,-9,2,6,5,-11,1,-2,6,

%T -1,3,-14,-4,-15,-1,10,8,12,1,-18,9,12,2,-20,-6,-21,5,4,11,-23,1,-3,2,

%U 16,6,-26,1,20,3,18,14,-29,-4,-30,15,6,-1,24,-10,-33,8,22,-12,-35,1,-36,18,4,9,30,-12,-39,2,-1,20

%N Dirichlet convolution of A003602 (Kimberling's paraphrases) with A055615 (Dirichlet inverse of n)

%C Dirichlet convolution of this sequence with A000010 gives A349136, which also proves the formula involving A023900.

%C Convolution with A000203 gives A349371.

%H Antti Karttunen, <a href="/A349431/b349431.txt">Table of n, a(n) for n = 1..20000</a>

%F a(n) = Sum_{d|n} A003602(n/d) * A055615(d).

%F a(n) = A023900(n) when n is a power of 2, and a(n) = A023900(n)/2 for all other numbers.

%F a(n) = -A297381(n).

%t k[n_] := (n / 2^IntegerExponent[n, 2] + 1)/2; a[n_] := DivisorSum[n, # * MoebiusMu [#] * k[n/#] &]; Array[a, 100] (* _Amiram Eldar_, Nov 18 2021 *)

%o (PARI)

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

%o A055615(n) = (n*moebius(n));

%o A349431(n) = sumdiv(n,d,A003602(n/d)*A055615(d));

%o (PARI)

%o A023900(n) = factorback(apply(p -> 1-p, factor(n)[, 1]));

%o A349431(n) = if(!bitand(n,n-1),A023900(n),A023900(n)/2);

%Y Sequence A297381 negated.

%Y Cf. A003602, A023900, A055615, A297381, A349432 (Dirichlet inverse), A349433 (sum with it).

%Y Cf. also A000010, A000203, A349136, A349371, and also A349444, A349447.

%K sign

%O 1,5

%A _Antti Karttunen_, Nov 17 2021

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 12 17:16 EDT 2024. Contains 373339 sequences. (Running on oeis4.)