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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A349376 Dirichlet convolution of A006368 with the Dirichlet inverse of A006369, where A006368 is the "amusical permutation", and A006369 is its inverse permutation.

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%I A349376 #8 Nov 25 2021 19:39:05
%S A349376 1,0,0,1,-3,5,-4,-2,1,11,-7,-7,-7,14,7,4,-10,2,-11,-22,10,25,-14,16,7,
%T A349376 25,0,-26,-17,-41,-18,-8,17,36,34,7,-21,39,17,52,-24,-52,-25,-48,1,50,
%U A349376 -28,-36,8,-51,24,-48,-31,7,62,60,27,61,-35,136,-35,64,0,16,62,-93,-39,-70,34,-178,-42,-26,-42,75,-27,-74
%N A349376 Dirichlet convolution of A006368 with the Dirichlet inverse of A006369, where A006368 is the "amusical permutation", and A006369 is its inverse permutation.
%C A349376 Obviously, convolving this sequence with A006369 gives its inverse A006368 from n >= 1 onward.
%H A349376 Antti Karttunen, <a href="/A349376/b349376.txt">Table of n, a(n) for n = 1..20000</a>
%F A349376 a(n) = Sum_{d|n} A006368(d) * A349368(n/d).
%o A349376 (PARI)
%o A349376 A006368(n) = ((3*n)+(n%2))\(2+((n%2)*2));
%o A349376 A006369(n) = if(!(n%3),(2/3)*n,(1/3)*if(1==(n%3),((4*n)-1),((4*n)+1)));
%o A349376 memoA349368 = Map();
%o A349376 A349368(n) = if(1==n,1,my(v); if(mapisdefined(memoA349368,n,&v), v, v = -sumdiv(n,d,if(d<n,A006369(n/d)*A349368(d),0)); mapput(memoA349368,n,v); (v)));
%o A349376 A349376(n) = sumdiv(n,d,A006368(d)*A349368(n/d));
%Y A349376 Cf. A006368, A006369, A349368, A349377 (Dirichlet inverse), A349378 (sum with it).
%Y A349376 Cf. also pairs A349613, A349614 and A349397, A349398 for similar constructions.
%K A349376 sign
%O A349376 1,5
%A A349376 _Antti Karttunen_, Nov 17 2021