the B10-15 example is easy: B1[0-5] (character class), as is B120-125 (B12[0-5]). As you say, logic spanning B18-24 is more difficult; that's why I broke it into 2 regexs in my post above. It was easier to match B1[8-9] or B2[0-4] than to try some regex-fu. You may be more adept with regexes than I am.
update: escape out [ ] so they're visible.
in reply to Re^2: matching numeric range
in thread matching numeric range