Interestingly, there a couple connections between Beethoven and Mendelssohn
that seem too exact to be coincidences.

Opening of Beethoven's Op. 1, No. 1 piano trio (1st mvt.) and the opening
of Mendelssohn's string octet (although the theme is only an arpeggio, it
still sounds "taken" to me)

The main arpeggio theme (in d minor) of Beethoven's "Tempest" piano sonata
(1st mvt.) and Mendelssohn's first piano quartet (1st mvt.) -- here, it is
also certain that Mendelssohn took the primary theme of his movement from
Beethoven's sonata

Hope this was understandable!

Jeff Grossman
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