OFFSET
0,3
FORMULA
E.g.f.: Product_{j>=1} (1 + Sum_{i>=1} x^(i*j) / i).
MATHEMATICA
nmax = 21; CoefficientList[Series[Product[1 - Log[1 - x^k], {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!
nmax = 21; CoefficientList[Series[Product[(1 + Sum[x^(i j)/i, {i, 1, nmax}]), {j, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Nov 30 2019
STATUS
approved