Dates of periapsis of Jupiter and Saturn

wrote in news:ec744251-9eb1-4790-b43a-
:

According to my calculations, Saturn passes Jupiter in its orbit once
every twenty Earth years. Can anyone give me a list of years when this
periapsis will happen? I'm particularly interested in the late 24th
century.

I would be interested in knowing of a resource that would let me
predict the positions of the planets in our solar system for several
centuries to come.

I don't think that's periapsis, but opposition, and you have to be
careful when using that word, because it's opposition with each other.
If you leave out the words "with each other" and just say "opposition"
the default assumption is opposition with the Earth, which is not what
you're interested in.

Periapsis is the point of closest approach of one body orbiting another.
Since Jupiter and Saturn orbit the sun, periapsis is the same thing as
perihelion. They don't have a mutual periapsis, because they don't
orbit each other.