Distribution ensemble

In cryptography, a distribution ensemble or probability ensemble is a family of distributions or random variables ${\displaystyle X=\{X_{i}\}_{i\in I}}$ where ${\displaystyle I}$ is a (countable) index set, and each ${\displaystyle X_{i}}$ is a random variable, or probability distribution. Often ${\displaystyle I=\mathbb {N} }$ and it is required that each ${\displaystyle X_{n}}$ have a certain property for n sufficiently large.

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