Can one find an algorithm whose running time is larger than Ackermann's function?

Question

Is there an example of an algorithm whose time complexity is strictly larger than Ackermann's function?

Answer 1

$A(n,n)$ is computable. So a trivial algorithm with complexity $O(A(n,n)^2)$ is the following:

1. Compute $x = A(n,n)$.
2. Loop $x^2$ times, doing nothing.