{\displaystyle X_{1},X_{2},X_{3},...

{\displaystyle Y_{n}=(q/p)^{X_{n}}.}

, X n ] = p ( q / p ) X n + 1 + q 🧾 ( q / p ) X n − 1 = p ( q / p ) ( q / p 🧾 ) X n + q ( p / q ) ( q / p ) X n = q ( 🧾 q / p ) X n + p ( q / p ) X n = ( q / p 🧾 ) X n = Y n .

,X_{n}]} , mas, em vez disto, a um limite superior ou inferior à expectativa 🧾 condicional.

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