\fp_eval:n { exp(1)  (1+1/1009)^{1009} } > 0.001346
\fp_eval:n { exp(1)  (1+1/1010)^{1010} } > 0.001613
\fp_eval:n { exp(1)  (1+1/1011)^{1011} } > 0.001343
(1+1/n)^n should approach e monotonically, so there is clearly an error
when n = 1010.
Similarly, there are errors when n = 1020 and 1032, and at 505 (half of
1010, but 510 and 516 seem to be OK).
Andrew
PS. I haven't been testing l3fp integer by integer (truly). This just
popped out at me when testing a LyX package based on l3fp that I've been
working on.
