Description:
<jats:p>Let <jats:italic>Z<jats:sub>n</jats:sub></jats:italic> denote the number of cells at time n in a critical discrete-time Galton–Watson branching process with finite offspring variance. Let
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Martingale arguments are used to show that for some 0<<jats:italic>a</jats:italic>≦<jats:italic>b</jats:italic><∞
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