#### Liam

##### New member

in ai = Hagg(L,Xi) what do we hash? Is it the all public keys (L) "concatenated" together then public key i "concatenated" at the end?

Don't think this makes a difference if consistency is kept but are pub keys in compressed form or uncompressed?

For example with 2 keys is it calculated like this (so hash of a 99 byte long array: 3*(1+32compressed))?:

a1=Hash(pub1 || pub2 || pub1)

a2=Hash(pub1 || pub2 || pub2)

Similarly for calculation of 'c' is it again concatenation of bytes, also are the points (X~ and R) in their compressed form or uncompressed (again I don't think it makes a difference but want to make sure)?

c = Hsig(X~ ,R,m)

Also I am assuming Hsig, Hagg,.. are all the same hash function like SHA256.

And finally in verification step shouldn't it be R + X~ in the following equation since they are both points, multiplication doesn't make any sense?