Algorithmic aspects of Lipschitz functions
  We characterize the variation functions of computable Lipschitz functions. We show that a real z is computably random if and only if every computable Lipschitz function is differentiable at z. Beyond these principal results, we show that a real z is Schnorr random if and only if every Lipschitz function with $L_1$-computable derivative is differentiable at z. 
Cameron Freer, Bj{\o}rn Kjos-Hanssen, Andr\'e Nies, Frank Stephan
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