What is the recommended
nSequence for signalling RBF transactions?
A transaction is considered to have opted in to allowing replacement of itself if any of its inputs have an nSequence number less than (0xffffffff - 1).
What is the recommended policy—is it better to send smaller or higher
Also, does the sequence number need to increase with newer "versions" of the transaction with higher fees, as was the original semantics of
nSequence, or not?
Bitcoin Core itself uses
nSequence=0, but only in the RBF tests, AFAIK.