A280075 Partial products of A211776 (Product_{d|n} tau(d)).

1, 2, 4, 24, 48, 768, 1536, 36864, 221184, 3538944, 7077888, 2038431744, 4076863488, 65229815808, 1043677052928, 125241246351360, 250482492702720, 72138957898383360, 144277915796766720, 41552039749468815360, 664832635991501045760, 10637322175864016732160

Offset: 1

Author

Jaroslav Krizek, Dec 25 2016

Keywords

• nonn

Comments

tau(n) is the number of positive divisors of n (A000005).

Crossrefs

Cf. A000005, A175596 (partial products of A007425), A237349 (partial sums of A211776).

Programs

Magma

[&*[&*[NumberOfDivisors(d): d in Divisors(k)]: k in [1..n]]: n in [1..100]]

Mathematica

FoldList[Times, Table[Product[DivisorSigma[0, d], {d, Divisors@ n}], {n, 22}]] (* Michael De Vlieger, Dec 25 2016 *)

Formula

a(n) = prod_{i=1..n} A211776(i).