Find a formula for the nth term of the sequence in terms of n. one ninth comma two twelfths comma StartFraction 2 squared Over 15 EndFraction comma StartFraction 2 cubed Over 18 EndFraction comma StartFraction 2 Superscript 4 Over 21 EndFraction comma ... 1 9 , 2 12 , 22 15 , 23 18 , 24 21 , ... a Subscript n an equals = nothing for n greater than or equals 1 n≥1