Beethoven did in fact rework his violin concerto into a piano concerto,
but nowhere is this referred to as "Concerto #6." Robbins Landon mentions
some sketches for a sixth concerto and laments the fact that no patron or
publisher pushed the issue to make LvB finish it.  There have been at least
two recordings of it, one with Felicja Blumental and one with Peter Serkin.

Aaron J. Rabushka
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