Pseudo-random generators, for sure, which are entirely deterministic. It does not even matter if you had a source of truly random numbers. Given the same sequen

Pseudo-random generators, for sure, which are entirely deterministic. It does not even matter if you had a source of truly random numbers. Given the same sequence of numbers, an algorithm will return the same result. That is what it means to be a function. The problem is not that, "my answer must be 'unpredictable'", but, "the actual answer may not be computable" (and so, no algorithm may ever derive it).