Implied fwd rates L3

Can someone help me refresh my memory of these calcs frm L1/L2

Below is from an ecosystem Q. If the question said to calculate the 1 yr implied rate, say 3 yrs fwd (and say we were given the 3 yr rates instead), how would the formula change? Further, can we expect Qs like this for L3? Thanks!

To calculate the 1-year forward rate starting three years from now, you need the 3-year spot rate and the 4-year spot rate:

_1f_3 = \frac{\left(1 + s_4\right)^4}{\left(1 + s_3\right)^3} - 1

ah perfect, thanks!

My pleasure.