What is the 1000th term in the series 0, 7, 14, 21, … ?

Map this out as a function with term number n and value
1, 0
2, 7
3, 14
4, 21

The values jump by 7, but they do so as the n - 1 term.

We have the series formula S(n) = 7(n - 1)

The problem asks for S(1000)
S(1000) = 7(1000 - 1)
S(1000) = 7(999)
S(1000) = 6,993