The only IQH question I will EVER make, this was given to me... Explanation: This is a combination of both ideas I had for this one. One involved 128 = -128 (signed mod 256), and the other involves PLN. Q128, in this context, is read as an expression in PLN. They were also using an 8-bit system, so this is actually Q-128. However, most logic was unsigned. Because of this, the comparison passed, meaning the computer started to compute FS(ε0, -128), which broke it. OTHERS: "THE PARADOX OF SELFREFERENCE" - Define a set S as all sets K where K ∉ K. If S ∉ S, then S includes S. But then K ∉ K is false for K = S, so S doesn't include itself. Paradox. It's the same here. You are answering Q128, which they couldn't find the answer to. Paradox. "IT WAS A QUINTIC" - You have heard of the quadratic formula, right? There's also a cubic formula, which birthed the idea of the complex plane. There's even a quartic formula, but that's a god awful formula that's impossible to write in one line. Well, you might think "If there are solutions for quadratics, cubics, and quartics, then why not any degree?" Well, too bad. You can use Group theory to create a new type of theory called Galois theory, and using that you can prove that all solvable polynomials must have their roots have symmetries equivalent to that of rotations and/or reflections of regular polygons. What does this mean for the quintic? Well, there is an infinite family of root symmetries that a general solution for a degree N polynomial must be made of these polygonal symmetries - the symmetries of permutations. It turns out that the permutations of order 5 is made of flipping and alternations of order 5 - which can't be made from polygonal symmetries. Q.E.D. "Q128 IS ILL-DEFINED" - Bower's Exploding Array Function is infamous for being ill-defined pasted tetrational arrays. "GET A DEGREE IN ORDINALOGY" - The hint. "DEFINE {#,##,1,2}" - There's something similar here. Sbiis Saibian says that repeating {#,#+1,1,2} can't lead to {#,#+2,1,2} because it breaks his theory of the climbing.