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Partial products of A206032 (Product_{d|n} sigma(d)).
2

%I #9 Sep 08 2022 08:46:18

%S 1,3,12,252,1512,217728,1741824,548674560,28531077120,9244068986880,

%T 110928827842560,3130855237028413440,43831973318397788160,

%U 25247216631397125980160,14542396779684744564572160,142006504553621530673047142400,2556117081965187552114848563200

%N Partial products of A206032 (Product_{d|n} sigma(d)).

%C sigma(n) is the sum of the divisors of n (A000203).

%F a(n) = Product_{i=1..n} A206032(i).

%t FoldList[Times[#1, #2] &, Array[Product[DivisorSigma[1, d], {d, Divisors@ #}] &, 17]] (* _Michael De Vlieger_, Dec 26 2016 *)

%o (Magma) [&*[&*[SumOfDivisors(d): d in Divisors(k)]: k in [1..n]]: n in [1..100]]

%Y Cf. A000203, A007429, A206032, A280078 (partial products of A007429), A280085 (partial sums of A206032).

%K nonn

%O 1,2

%A _Jaroslav Krizek_, Dec 26 2016