Here any three consecutive numbers means every three consecutive numbers.
For Eg. if the four digit number is abcd then (abc) itself has to be a three digit prime and also (bcd) should also be a three digit prime.
Taking the example for n = 5 let the 5 digit number be abcde then (abc) itself has to be a three digit prime, (bcd) should also be a three digit prime and at last (cde) should also be a three digit prime.

If any of the problem setter reads this then please clarify clearly about this. As I was stuck on this for almost 2 days, by pondering how come the answer for n = 4 is 204 while even bruteforce was giving me 2513.

Edited by author 09.11.2020 11:45

Edited by author 09.11.2020 11:45