^^ Sorry. I made a big mistake. We cannot substitute of course.

Maybe would work as an approximation, because we know that tends very rapidly to a line on logarithmic scale. Anyways, it would be of little use.

We know that the are the derivatives of , so a Fourier or Laplace transform would turn the derivatives into products. But that would mess with the rest of the equation.

Maybe would work as an approximation, because we know that tends very rapidly to a line on logarithmic scale. Anyways, it would be of little use.

We know that the are the derivatives of , so a Fourier or Laplace transform would turn the derivatives into products. But that would mess with the rest of the equation.

I have the result, but I do not yet know how to get it.