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A349377
Dirichlet convolution of A006369 with the Dirichlet inverse of A006368, where A006368 is the "amusical permutation", and A006369 is its inverse permutation.
8
1, 0, 0, -1, 3, -5, 4, 2, -1, -11, 7, 7, 7, -14, -7, -3, 10, -2, 11, 16, -10, -25, 14, -6, 2, -25, 0, 18, 17, 11, 18, 4, -17, -36, -10, 20, 21, -39, -17, -18, 24, 12, 25, 34, -7, -50, 28, 2, 8, -15, -24, 34, 31, 3, -20, -16, -27, -61, 35, 30, 35, -64, -8, -5, -20, 23, 39, 50, -34, 6, 42, -44, 42, -75, -15, 52, -22, 23
OFFSET
1,5
COMMENTS
Obviously, convolving this sequence with A006368 gives its inverse A006369 from n >= 1 onward.
LINKS
FORMULA
a(n) = Sum_{d|n} A006369(d) * A349351(n/d).
a(n) = A349378(n) - A349376(n).
PROG
(PARI)
A006368(n) = ((3*n)+(n%2))\(2+((n%2)*2));
A006369(n) = if(!(n%3), (2/3)*n, (1/3)*if(1==(n%3), ((4*n)-1), ((4*n)+1)));
memoA349351 = Map();
A349351(n) = if(1==n, 1, my(v); if(mapisdefined(memoA349351, n, &v), v, v = -sumdiv(n, d, if(d<n, A006368(n/d)*A349351(d), 0)); mapput(memoA349351, n, v); (v)));
A349377(n) = sumdiv(n, d, A006369(d)*A349351(n/d));
CROSSREFS
Cf. A006368, A006369, A349351, A349376 (Dirichlet inverse), A349378 (sum with it).
Cf. also pairs A349613, A349614 and A349397, A349398 for similar constructions.
Sequence in context: A317190 A317191 A165109 * A349376 A134892 A253074
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 17 2021
STATUS
approved