Primorials are like Factorials except that only the prime numbers are multiplied:
2, 6, 30, 210, 2310, 30030, ...

Starting with the first primorial which is at least two digits, consider a sequence composed of the second to last digit of each primorial:
3, 1, 1, 3 ...
The first digit of this sequence is '3'.

Please provide the 999th and 9999th digits of this sequence.