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A349614
Dirichlet convolution of A064664 (the inverse permutation of EKG-permutation, A064413) with the Dirichlet inverse of A064413.
9
1, 0, 1, -3, 7, -7, 2, 6, -8, -10, 5, 9, 14, 2, -41, -1, 17, 27, 15, -6, -38, -18, 13, 10, -32, -29, 18, 33, 18, 62, 29, -13, -31, -53, -107, 25, 48, -51, -86, 13, 30, 116, 58, 23, 88, -34, 37, -47, -30, 56, -113, 3, 45, -39, -137, -154, -73, -67, 41, 160, 84, -91, 174, 56, -154, 152, 91, 6, -113, 246, 58, -185, 56
OFFSET
1,4
COMMENTS
Obviously, convolving this with A064413 gives its inverse permutation A064664.
FORMULA
a(n) = Sum_{d|n} A064664(d) * A349400(n/d).
PROG
(PARI)
up_to = 32768;
v064413 = readvec("b064413_upto65539_terms_only.txt"); \\ Data prepared with Chai Wah Wu's Dec 08 2014 Python-program given in A064413.
A064413(n) = v064413[n];
\\ Then its inverse A064664 is prepared:
m064664 = Map();
for(n=1, 65539, mapput(m064664, A064413(n), n));
A064664(n) = mapget(m064664, n);
memoA349400 = Map();
A349400(n) = if(1==n, 1, my(v); if(mapisdefined(memoA349400, n, &v), v, v = -sumdiv(n, d, if(d<n, A064413(n/d)*A349400(d), 0)); mapput(memoA349400, n, v); (v)));
A349614(n) = sumdiv(n, d, A064664(d)*A349400(n/d));
CROSSREFS
Cf. A064413, A064664, A349400, A349613 (Dirichlet inverse), A349615 (sum with it), A349617.
Cf. also pairs A349376, A349377 and A349397, A349398 for similar constructions.
Sequence in context: A131608 A131707 A348722 * A349613 A016620 A200691
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 23 2021
STATUS
approved