- (A) is a subset of (A)
- (A,B) is a subset of (A,B,C)
- (B,A) is not a subset of (A,B,C) because order matters.
- (B,C) is not a subset of (A,B,C) because I only want to compare the front of each set.
Now subset is the second cousin of the word I'm actually looking for. Which word would best fit here?
- is a prefix of
... but they seem awkward. Bonus points if there's a common term with an accepted Mathematical meaning (I'm not sure if some term exists).