Elements of Wigner’s Proof
	v Compute E(A2k)11= mean(l2k) = (2k)th moment v Verify that the semicircle is the only distribution with these moments v (A2k)11 = SA1xAxy…AwzAz1 “paths” of length 2k v Need only count number of special paths of length 2k on k objects  (all other terms 0 or negligible!) v This is a Catalan Number!