MathDB

A serie of positive integers

a_{1}

a_{2}

,. . . ,

a_{n}

auto-delimited

if for every index

i

that holds

1\leq i\leq n

, there exist at least

a_{i}

terms of the serie such that they are all less or equal to

i

. Find the maximum value of the sum

a_{1}+a_{2}+\cdot \cdot \cdot+a_{n}

, where

a_{1}

a_{2}

,. . . ,

a_{n}

is an

auto-delimited

serie.

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