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A349393
Inverse Möbius transform of A126760.
10
1, 2, 2, 3, 3, 4, 4, 4, 3, 6, 5, 6, 6, 8, 6, 5, 7, 6, 8, 9, 8, 10, 9, 8, 12, 12, 4, 12, 11, 12, 12, 6, 10, 14, 18, 9, 14, 16, 12, 12, 15, 16, 16, 15, 9, 18, 17, 10, 21, 24, 14, 18, 19, 8, 26, 16, 16, 22, 21, 18, 22, 24, 12, 7, 30, 20, 24, 21, 18, 36, 25, 12, 26, 28, 24, 24, 34, 24, 28, 15, 5, 30, 29, 24, 38, 32, 22
OFFSET
1,2
LINKS
FORMULA
a(n) = Sum_{d|n} A126760(d).
MATHEMATICA
f[n_] := 2 * Floor[(m = n/2^IntegerExponent[n, 2]/3^IntegerExponent[n, 3])/6] + Mod[m, 3]; a[n_] := DivisorSum[n, f[#] &]; Array[a, 100] (* Amiram Eldar, Nov 16 2021 *)
PROG
(PARI)
A126760(n) = {n&&n\=3^valuation(n, 3)<<valuation(n, 2); n%3+n\6*2}; \\ From A126760
A349393(n) = sumdiv(n, d, A126760(d));
(PARI) a(n)=my(a=valuation(n, 2), b=valuation(n, 3), c=(a+1)*(b+1)); sumdiv(n/3^b>>a, d, d\6*2+d%3)*c; \\ Charles R Greathouse IV, Nov 16 2021
CROSSREFS
Cf. A347233, A347234, A349390, A349391, A349392, A349395 for other Dirichlet convolutions of A126760. And also A349371.
Sequence in context: A238701 A238134 A143489 * A341155 A341166 A274102
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 16 2021
STATUS
approved