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Equation 42 · Part 2 · Why Coding Agents Fail: Long-Horizon Reliability in OpenAI Codex

subscript

did_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

Checkpoint placement is a value-of-information problem. Let an unchecked latent error at stage i create expected downstream loss LiL_i , a check cost KiK_i , detection probability did_i , and false-alarm cost FiF_i . A check is favorable when, approximately,

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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 →

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