Is the this geometric, arithmetic, or neither

Question

7/n²

Answer 1

a1 = 7/1^2 = 7

Neither

a1 = 7

a2 = 7/4

a3 = 7/9

a4 = 7/16

to be arithmetic, there has to be a common difference = d = a2-a1 = a3-a2 =7/4-7 = 7/9-7/4. That's not true. it's not arithmetic

to be geometric there has to be a common ratio= r. a2 = a1(r) 7/4 = 7(1/4) 7/9 =7/4(1/4) which isn't true either.

It's not arithmetic or geometric.