A sequence of positive real numbers $\{a_1, a_2, a_3, \dots\}$ has the property that for $i \ge 2,$ each $a_i$ is equal to the sum of all the previous terms.  If $a_{19} = 99,$ then what is $a_{20}$?
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<|im_start|>user
A sequence of positive real numbers $\{a_1, a_2, a_3, \dots\}$ has the property that for $i \ge 2,$ each $a_i$ is equal to the sum of all the previous terms.  If $a_{19} = 99,$ then what is $a_{20}$?
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A sequence of positive real numbers $\{a_1, a_2, a_3, \dots\}$ has the property that for $i \ge 2,$ each $a_i$ is equal to the sum of all the previous terms.  If $a_{19} = 99,$ then what is $a_{20}$?
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