Original Cin

My roommate and I were discussing pseudorandom number generators. Since I’m not particularly good at math, he stumped me for a while by asking how a sequence of numbers from a generator compares to real random numbers (like, for instance, numbers generated from radioactive decay).

It turns out that my roommate could have stumped someone with a lot more knowledge with his question: Wikipedia notes “It is an open question, and one central to the theory and practice of cryptography, whether there is any way to distinguish the output of a high-quality PRNG from a truly random sequence without knowing the algorithm(s) used and the state with which it was initialized.” Of course, some sequences of numbers generated by a less than perfect PRNG are almost certainly not random.