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A280085
Partial sums of A206032 (Product_{d|n} sigma(d)).
2
1, 4, 8, 29, 35, 179, 187, 502, 554, 878, 890, 29114, 29128, 29704, 30280, 40045, 40063, 113071, 113091, 208347, 209371, 210667, 210691, 25612291, 25612477, 25614241, 25616321, 25842113, 25842143, 52715999, 52716031, 53331226, 53333530, 53336446, 53338750
OFFSET
1,2
COMMENTS
sigma(n) is the sum of the divisors of n (A000203).
FORMULA
a(n) = Sum_{i=1..n} A206032(i).
MATHEMATICA
Accumulate@ Array[Product[DivisorSigma[1, d], {d, Divisors@ #}] &, 35] (* Michael De Vlieger, Dec 26 2016 *)
PROG
(Magma) [&+[&*[SumOfDivisors(d): d in Divisors(k)]: k in [1..n]]: n in [1..100]]
CROSSREFS
Cf. A000203, A007429, A206032, A280077 (partial sums of A007429), A280086 (partial products of A206032).
Sequence in context: A025234 A075308 A300461 * A322784 A297638 A256456
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Dec 26 2016
STATUS
approved