I did this while hiring last year and the number of candidates who got stuff wrong because they were too proud to just look up the answer was shocking.
Exactly. You never know. Some interviewers will penalize you for not having something memorized and having to look it up, some will penalize you for guessing, some will penalize you for simply not knowing and asking for help. Some interviewers will penalize you for coming up with something quick and dirty and then refining it, some will penalize you for jumping right to the final product. There's no consistency.
