Let G _n be the genus of a two-dimensional surface obtained by gluing, uniformly at random, the sides of an n-gon. Recently Linial and Nowik proved, via an enumerational formula due to Harer and Zagier, that the expected value of G _n is asymptotic to (n-logn)/2 for n→∞. We prove a local limit theorem for the distribution of G _n, which implies that G _n is asymptotically Gaussian, with mean (n-logn)/2 and variance (logn)/4.
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