Public evidence

math.sequences

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON MCP Review policy

Verification

12/12 calculation tests · Production surface contract 4/4

Golden tests 4 / 4
Boundary tests 2 / 2
Property tests 6 / 6
Production surface contract 4 / 4
Engine tested Yes
Source checked Yes
Artifact integrity PASS
Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (1 capability; 163 remain CURRENT) @ 2026-09-19T00:00:17.039Z
Semantic contract PASS
Evidence attested at 2026-09-18T21:41:55.460Z
Last production check 2026-09-18T21:41:55.460Z
Public / cache —
Origin —
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS

Fingerprint sha256:ac633fb6a40d747074c2c45a941fe716881af18188b8106d6e4ae77635cbed0e

Input schema sha256:f4bec45ebd1ac51417827dbf207258b1f2ccd72527597c58159b524c703e14a7 · Output schema sha256:01c274ed03ed17ad714cbc73df6bebd2b0870b9cfd46b35fac7435fc90e62232 · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: sequence
Engine: sequence
Engine build: 2026-09-19
Evidence core: 2026-09-19T01:08:38.526Z
Rendered: 2026-09-19T02:14:29.317Z
Last reviewed: —

Assumptions

Integers
n ≤ 1000
Not Pascal / partition / n!

Limitations

Not Pascal’s triangle and not integer partition
Not /calc/math/factorial and not /calc/math/permutation-combination
Integers only — no Binet float Fibonacci
Engine id is sequence; never alias the add/sub engine id arithmetic
n=0 on AP/GP → VALUE_MUST_BE_POSITIVE
n>1000 → VALUE_ABOVE_MAX
unknown mode → INVALID_MODE

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

ISO 80000-2:2019 Quantities and units — Mathematics

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`golden-ap`	golden	pass	Expected term=14 · sum=40 · Actual n=5 · d=3 · value=14 · mode=arithmetic · a=2 · term=14 · sum=40 · exact=14
`golden-gp`	golden	pass	Expected term=24 · sum=45 · Actual n=4 · value=24 · mode=geometric · a=3 · r=2 · term=24 · sum=45 · exact=24
`golden-fib-10`	golden	pass	Expected term=55 · Actual n=10 · value=55 · mode=fibonacci · term=55 · sum=143 · exact=55 · prev=34 · convention=F_0=0, F_1=1
`golden-recurrence-fib`	golden	pass	Expected term=55 · Actual n=10 · value=55 · mode=linear_recurrence · p=1 · q=1 · a0=0 · a1=1 · term=55
`boundary-seq-pascal`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`boundary-ap-n0`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`property-ap-term`	property	pass	a_5=14
`property-ap-sum`	property	pass	S_5=40
`property-gp-term`	property	pass	a_4=24
`property-fib-10`	property	pass	F_10=55
`property-rec-fib`	property	pass	recurrence matches F_10
`property-fib-0`	property	pass	F_0=0