If the next character were one that had never been encountered before, say t, escaping would take place repeatedly right down to the base level k = -1. Once this level is reached, all symbols are equiprobable-except that, through the exclusion device, there is no need to reserve probability space for symbols that already appear at higher levels. Assuming a 256-character alphabet, the t is coded with probability 1/251 at the base level, leading to a total requirement of 11.2 bits including those needed to specify the three escapes.

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