"Generate" and "Propagate" are referring to the names of the signals in the first stage of a carry-lookahead adder ( https://en.wikipedia.org/wiki/Carry-lookahead_adder ). Generate is A AND B (AB), Propagate is A OR B (A + B). This is also where the AND and OR for the logic functionality comes from.
The '181 has no clock input, the outputs will change after some propagation delay whenever an input changes.
The '181 has no clock input, the outputs will change after some propagation delay whenever an input changes.
This explanation of CLA adding may also help: https://www.cs.umd.edu/class/sum2003/cmsc311/Notes/Comb/look...