OFFSET
0,2
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..447
FORMULA
MATHEMATICA
nmax = 25; CoefficientList[Series[Product[(1 + x^(i*j)/(i*j)!)/(1 - x^(i*j)/(i*j)!), {i, 1, nmax}, {j, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!
nmax = 25; CoefficientList[Series[Product[((1 + x^k/k!)/(1 - x^k/k!))^DivisorSigma[0, k], {k, 1, nmax}], {x, 0, nmax}], x]*Range[0, nmax]!
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Feb 22 2021
STATUS
approved