https://www.astro.puc.cl/~rparra/tools/PAPERS/lorenz1962.pdf
However, the general concept was already known:
> Poincaré, 1903: “A very small cause which escapes our notice determines a considerable effect that we cannot fail to see, and then we say that the effect is due to chance. If we knew exactly the laws of nature and the situation of the universe at the initial moment, we could predict exactly the situation of that same universe at a succeeding moment. But even if it were the case that the natural laws had no longer any secret for us, we could still only know the initial situation approximately. If that enabled us to predict the succeeding situation with the same approximation, that is all we require, and we should say that the phenomenon had been predicted, that it is governed by laws. But it is not always so; it may happen that small differences in the initial conditions produce very great ones in the final phenomena. A small error in the former will produce an enormous error in the latter. Prediction becomes impossible, and we have the fortuitous phenomenon.”
Thus 'Seldon's equations of psychohistory' would almost certainly be subject to sensitive dependence on initial conditions, and would be no more useful than algorithms claiming to predict future financial market behavior, or the specific weather at a certain location on a year from now.
It's not really Asimov's fault - this was also an era when people believed they could learn how to steer hurricanes with minor energy inputs, another topic where chaos demonstrated why that would be impossible to do with any confidence.
However, it's also kind of hilarious that Seldon failed to predict fundamental changes in society (like women in leading academic or political positions), Asimov's vision is basically 1950s society projected into the future. I suppose some people have wistful longings for that era, but not me.