$42, 62, 67, 14, 27, 45, 4, 14\dots$
This is the number sequence which does not appear in OEIS and actually has little to do with maths. To find the next number, please look at the title and the tags!
Hint 1:
TREN (remember the code which is most frequently used here). Note that the both 14s in the sequence are in fact very different!
Hint 2:
The sequence resides in a (current) European country which didn't exist at the time when the sequence started.
Hint 3:
In the other sequences of this kind, the numbers are mostly single-digit, and almost never higher than 23.
Hint 4 (maybe decisive):
For every sequence $\{r_k\}$ of this kind, we usually can define a function $f:\mathbb{N}\to\mathbb{N}$, such as for all $k$ exist such indices $i_1<i_2<\dots<i_n=k$ where $f(r_{i_1})=f(r_{i_2})=\dots=f(r_{i_n})$ and $r_{i_j}=j$. (i.e. $r_{i_1}=1,r_{i_2}=2$ etc. up to $r_{i_n}=r_k=n$).
But there are exceptions. One of the most famous sequences of this kind fails on $r_{187}=21$, where there is no $i_{20}$ to define.
P.S. Despite strong mathematical language, the rule is actually quite simple.