3 Brazilian Journal of Physics, vol. 00, no. 0000, 01, 2009 when the terms of the symbolic sequence are correlated. In order to explore further aspects of a symbolic se- quence, let us consider it as an erratic trajectory and establish a correspondence with a diffusive process. For the case of two-symbol sequences, we associate the sym- bol “0” with a jump of unit length to the right and the symbol “1” with a jump of unit length to the left. That is, a random walk-like process. Using the previous prescription, we calculate the standard-deviation for i = 1 to N over 10 5 events as we can see in Fig. (3). We know that the slope α of this curve is one for a usual diffusion, but in the case of Fig.(3) α is greater than one. We also observed that α depends on µ . This behavior is shown in Fig.(4a). Note that for small values of µ ( µ < 3) the diffusion is anoma- lous, i.e., we have a superdiffusion, and for large values ( µ ≥ 3) the diffusion regimes tend to a usual diffusion. This behavior can be explained if we remember that for small values of µ , N$_{y}$ can be very large and consequently the walker can make large steps without changing the direction. When µ is large, this event becomes very rare because N$_{y}$ is in general small, making the walker change directions, producing a usual erratic trajectory. We may also connect α with q ∗ through the values of µ . In order to do this we evaluate the relation q ∗ versus µ as shown in Fig. (4b) and exhibit q ∗ versus α in Fig. (4c). We verified that by varying the value of µ we can pro- duce long-range correlations in symbolic sequences. This is evidenced by the nonlinear growing of the Boltzmann- Gibbs entropy. This feature led us to use the Tsallis entropy with suitable values of q to obtain a satisfactory description of these sequences. Specifically, we observed that the Tsallis entropy preserves the extensivity even We also considered the symbolic sequence as a random walk-like process and evaluated the standard deviation. The result showed that the diffusive process presents a superdiffusive regime which emerges for small values of µ ( µ < 3). The usual diffusion is recovered when µ ≥ 3. The authors thank CENAPAD-SP (Centro Nacional de Processamento de Alto Desempenho em S˜ ao Paulo) for the computational support and the CNPq/INCT-SC for financial support. Acknowledgements 4. DISCUSSION AND CONCLUSION FIG. 4: (a) The α slope of the curve in Fig (3) versus µ (b) the entropic index q ∗ versus µ and (c) q ∗ versus α . In the three figures we use A = 0 . 1. 3. DIFFUSION AND SEQUENCE FIG. 3: The standard-deviation versus N for µ = 2 . 2 and A = 0 . 1. 10 4 10 5 10 6 10 7 10 8 10 9 10 10 0 10 1 10 2 10 3 2 N =2.2 1.00 1.20 1.40 1.60 1.80 2.2 2.4 2.6 2.8 3.0 (a) 0.98 0.99 1.00 2.2 2.4 2.6 2.8 3.0 q* (b) 0.98 0.99 1.00 1.0 1.2 1.4 1.6 1.8 q* (c)