A good problem for a recurrent network
We can train a feedforward net to
do binary addition, but there are
obvious regularities that it cannot
capture:
We must decide in advance the
maximum number of digits in
each number.
The processing applied to the
beginning of a long number
does not generalize to the end
of the long number because it
uses different weights.
As a result, feedforward nets do
not generalize well on the binary
addition task.

11001100
hidden units
00100110
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