What's the next number in the following sequence?
1, 3, 6, 7, 9, 11, 13, 14, 18, 21, 23, 28, 31, ___, ...
Hints will be released gradually - the first one is in the title.
Hint #2:
Depending on where you live, you may have never seen these numbers.
Additionally:
Never seeing these numbers is in fact an advantage, not a disadvantage.
Hint #3:
No math is involved (except for counting).
Hint #4:
The human brain may not be enough. Ask Google or Wikipedia for help.
Final Hint:
How do you search using Google for a sequence that you've never seen, or even has never existed? Google is not powerful enough to find something non-existent for you. You need to search for something else.