Ending index or upper bound: n

The passage around this formula

…a documented 1.25 times the base price of an input token; a cache read, on every subsequent turn that reuses it, costs a documented one-tenth of that base price [ 5 ] . For a stable prefix of $T_p$ tokens reused across n turns of a session, against a per-token base price c , the total cost of that prefix is $\mathrm{Cost}_n = 1.25\,c\,T_p + (n-1)\,(0.1\,c\,T_p) + c\sum_{i=1}^{n} T_{v,i}$. where the final sum covers each turn’s own variable content. Past the first turn, every further read of the same CLAUDE.md content costs a tenth of an uncached read — caching is…

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