The answer is 2n (-1)^(n + 1)
The numerator seems to be accelerated via 7 each and every time, so if it starts with the 1st term being one, it incredibly is secure to declare the nth numerator is 7^(n-a million) Likewise, the backside has a million, a million2, a million23, a million234, and a million234*5. This seems to be factorials, so we are in a place to declare the nth term interior the denominator is n! putting those mutually, the nth term is 7^(n-a million)/n!
I hope this helped God Bless!