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A328706 Dirichlet g.f.: Product_{k>=2} (1 + k^(-s))^2. 0
1, 2, 2, 3, 2, 6, 2, 6, 3, 6, 2, 12, 2, 6, 6, 9, 2, 12, 2, 12, 6, 6, 2, 24, 3, 6, 6, 12, 2, 22, 2, 14, 6, 6, 6, 28, 2, 6, 6, 24, 2, 22, 2, 12, 12, 6, 2, 42, 3, 12, 6, 12, 2, 24, 6, 24, 6, 6, 2, 52, 2, 6, 12, 22, 6, 22, 2, 12, 6, 22, 2, 60, 2, 6, 12, 12, 6, 22, 2, 42 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Dirichlet convolution of A045778 with itself.

LINKS

Table of n, a(n) for n=1..80.

FORMULA

a(n) = Sum_{d|n} A045778(n/d) * A045778(d).

CROSSREFS

Cf. A045778, A301830.

Sequence in context: A107753 A197929 A326849 * A240090 A078224 A159688

Adjacent sequences:  A328703 A328704 A328705 * A328707 A328708 A328709

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Oct 26 2019

STATUS

approved

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Last modified May 31 07:14 EDT 2020. Contains 334747 sequences. (Running on oeis4.)