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DL-C15-C-001
Add the residual branch to the input.
DL-C15-C-002
Projection replaces the direct x path in the sum.
DL-C15-C-003
Concatenation adds widths.
DL-C15-C-004
Use gate * candidate + (1 - gate) * old.
DL-C15-C-005
Differentiate x with respect to itself.
DL-C15-C-006
Adding zero leaves the input unchanged.
DL-C15-C-007
Think of routes through the computation graph.