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Binomial carry reads the cursor rank rather than the list head · case 03

The bounded binomial carry certificate reports an incorrect current.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

A consolidation cursor sees ordered ranks and index i. Report whether to link now, current rank, carry rank, suffix retained after a link, triple-collision deferral, and link partner. In three equal consecutive ranks defer the first pair so a carry is not consolidated twice out of order. Empty cursor is allowed.

Why this case matters

This isolates an internal heap representation or priority-structure invariant using deterministic finite records.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression certificate 4	`{"carry_rank": 2, "current": 0, "defer": false, "link_now": true, "partner": 2, "suffix": [3]}`	`{"carry_rank": 2, "current": 1, "defer": false, "link_now": true, "partner": 2, "suffix": [3]}`	Failed

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