If tn = n2 + 1, n ≤ 1,

show the first four terms of the pattern.
so far i got 2 1 0 -3. but it marked it wrong..and i don't know why

I think your formula should say

tn = n^2 + 1 , n > 1

tn is the usual terminology for "term number n"
of course n would have to be a whole number,
and an expression such as term "number minus 4" does not make a lot of sense.

so the first n you could use is n = 2
and your first 4 terms would be
5, 10, 17, and 26

let me know if the input accepted those values.