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Equation 31 · Part 5 · The Economics and Physical Limits of Running AI Agents at Scale

subscript

q1−q∑ici\frac{q}{1-q}\sum_i c_i
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

Holding qiq_i = q constant across the trajectory — a simplification, since real failure rates are neither constant nor independent — the expected extra cost from retries is q1−q\frac{q}{1-q}∑i\sum_i cic_i , and because cic_i increases with i , that extra cost is weighted toward the trajectory’s most expensive, latest steps rather than distributed evenly across it. A one-percent per-step retry rate is a rounding error at step five. Applied at step two hundred of an uncached or lightly cached loop, it is a rounding error on a much larger number.

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

Open the illustrated subscripts: which member of a family? guide →

Sources cited in the article section

These citations provide research context; check each source for the exact claim it supports.