How to express I2=log(sum(inv_pos()))

Hello, everyone! How can I express I2 ?
Constraint: I1 - I2-r0>=C0
r0 and C0 are both real value. sk(1,N) is variable.

for i=1:N
I1= -sum(a);

Thank you for your attention very much!

Doesn’t your previous topic Log-sum-inv,is it right address this?

Yes, I have deduced Log-sum-inv. But it is complicated, is there a simpler expression ?

The two formulations I know of are provided in section 5.2.7 Log-sum-inv of

That’s all right, thank you Mark!