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A349566
Dirichlet convolution of A011782 (2^(n-1)) with A349451 (Dirichlet inverse of Fibonacci numbers).
6
1, 1, 2, 4, 11, 20, 51, 100, 218, 441, 935, 1862, 3863, 7751, 15742, 31648, 63939, 128180, 257963, 516974, 1037502, 2078417, 4165647, 8339900, 16702136, 33428943, 66911942, 133891584, 267921227, 536021340, 1072395555, 2145272320, 4291440670, 8584166169, 17170641321, 34344672290, 68695318919, 137399603159, 274814652766
OFFSET
1,3
COMMENTS
Dirichlet convolution of this sequence with A034748 produces A034738.
LINKS
FORMULA
a(n) = Sum_{d|n} 2^(d-1) * A349451(n/d).
MATHEMATICA
s[1] = 1; s[n_] := s[n] = -DivisorSum[n, s[#] * Fibonacci[n/#] &, # < n &]; a[n_] := DivisorSum[n, 2^(# - 1) * s[n/#] &]; Array[a, 40] (* Amiram Eldar, Nov 22 2021 *)
PROG
(PARI)
memoA349451 = Map();
A349451(n) = if(1==n, 1, my(v); if(mapisdefined(memoA349451, n, &v), v, v = -sumdiv(n, d, if(d<n, fibonacci(n/d)*A349451(d), 0)); mapput(memoA349451, n, v); (v)));
A349566(n) = sumdiv(n, d, (2^(d-1)) * A349451(n/d));
CROSSREFS
Cf. A000045, A011782, A349451, A349565 (Dirichlet inverse).
Sequence in context: A076636 A011954 A278446 * A026275 A152597 A320679
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 22 2021
STATUS
approved