FA-63705 / Actuarial life tables / Member archive

Abridged period life table: Group mortality can exceed one · case 05

Very high mortality groups produce negative survivors.

Member previewVariant 5 · 3 implementations · 7 checks per implementation

Case contract

Input groups [[width n (None = open), deaths, population (<=0 -> 'invalid population'), nax as [num, den] years]]. m = deaths/pop; closed nqx = min(1, n m/(1+(n-a) m)), nLx = n l_{x+n} + a d; open q=1, L = l/m (m=0 -> 'open interval without deaths'). Radix 100000. Return [q list rounded 6, e0 = sum L / radix rounded 4].

Why this case matters

Life-table arithmetic compounds across ages, so one misplaced index or assumption shifts every downstream value.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
high mortality group capped	`[[0.03861, 1.233766, 1.0], 1.7643]`	`[[0.03861, 1.0, 1.0], 2.888]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.