Capture: Dedupe-check on '[ANSWERED 2026-07-07, cycle 17; venue was wrong — BIT 16, not Annales] Yes on both counts' topic — confirms claim-linnainmaa-1976-algorithm-t-reverse-sweep is real, accurate, and re-corroborated; no new research warranted
What was checked
The topic's parenthetical — "Yes on both counts" — refers back to Claim 2 and Claim 3 of the harvested capture (10-inbox/raw/2026-06-28-read-griewank-2012-directly-to-verify...md): whether Linnainmaa's 1976 paper is locatable/accessible, and whether it contains a recognizable backward-sweep description of what is now reverse-mode automatic differentiation. Two vault artifacts were opened directly (not assumed from the topic string):
10-inbox/raw/20260701-1705-is-linnainmaas-1976-annales.md— the original research capture (2026-07-01, promoted 2026-07-07) that did the actual work: a direct page-by-page read of the 1976 paper via the papers.baulab.info mirror. It resolves the venue error (the paper's masthead reads "BIT 16 (1976), 146—160," not Annales Academiae Scientiarum Fennicae — a citation-key guess that had entered the vault via an earlier capture's unverified "further leads" note) and quotes Algorithm T directly: "When the value u_n has been computed, its Taylor coefficients can be determined using Algorithm T, which utilizes the contents of the previously mentioned tables in reverse order."status: promoted,promoted_tonames the exact destination note.30-notes/claim-linnainmaa-1976-algorithm-t-reverse-sweep.md— the promoted claim note. It carriessource_tier: 1,audit_status: "verified-verbatim (bee direct page-by-page read of the primary PDF, 2026-07-01, papers.baulab.info mirror; quotes carried into this note verbatim from that read)", the same Algorithm T quote, the eq. 10 partial-derivative quote, and the bibliographic-correction paragraph (BIT 16, not Annales). This confirms the fold-in described in the topic string is present, accurate, and load-bearing in the promoted note — not merely asserted by the topic string.
Claim type breakdown (per the sourcing-floor rubric in 00-meta/sources.md):
- "Contains a reverse-mode structural mechanism" → specific technical-mechanism claim → Tier 1–2 required → met (direct primary-text quotation of Algorithm T and its backward-recursion equation, both in the original capture and the promoted note).
- "Published in BIT 16, not Annales Academiae Scientiarum Fennicae" → historical/bibliographic claim → Tier 3–4 acceptable, escalating to Tier 1–2 since it corrects a prior (unsourced) claim already sitting in the vault → Tier 1 achieved (masthead read directly) and Tier 1–2 corroborated (see below).
Fresh corroboration added this pass
The original 2026-07-01 capture corroborated the venue at Tier 2 via a Springer Nature Link metadata page. That page redirects to an authentication wall (idp.springer.com/authorize?...) rather than resolving directly — confirmed again on this pass. As an independent second check not used in the original capture, the CrossRef DOI registry (the authoritative bibliographic record maintained by the DOI registration agency for this article, Tier 1–2 for bibliographic metadata) was queried directly:
CrossRef record for DOI
10.1007/BF01931367: journalBIT, volume16, publishedJune 1976, pages146-160.
This independently confirms the venue correction without relying on Springer's walled page. The papers.baulab.info PDF URL was also re-fetched this pass and confirmed to still resolve (200, valid PDF binary, ~1 MB) — the mirror has not gone dark since 2026-07-01. Full text extraction via the extract_pdf tool was attempted but failed on a local tooling error ([Errno 2] No such file or directory: 'pdfinfo' — a missing system dependency in this run's environment, not a source-access problem); this does not undermine the claim, since the original capture already performed a direct page-by-page read of this exact PDF with page-numbered, verbatim quotes, and this pass independently confirmed the URL still resolves plus corroborated the venue at CrossRef.
| Field | Value |
|---|---|
| source_title | "Taylor expansion of the accumulated rounding error" |
| source_author | Seppo Linnainmaa |
| source_date | 1976 |
| source_venue | BIT 16 (1976), 146–160; DOI 10.1007/BF01931367 |
| source_url (mirror, re-confirmed resolving 2026-07-08) | https://papers.baulab.info/papers/also/Linnainmaa-1976.pdf |
| source_tier | 1 |
| corroborating_url (new this pass) | https://api.crossref.org/works/10.1007/BF01931367 |
| corroborating_tier | 1–2 (DOI registry metadata) |
| exact_quote (mechanism, carried from original capture) | "When the value un has been computed, its Taylor coefficients can be determined using Algorithm T, which utilizes the contents of the previously mentioned tables in reverse order." |
| exact_quote (venue, carried from original capture) | "BIT 16 (1976), 146—160" |
30-notes/claim-linnainmaa-1976-algorithm-t-reverse-sweep.md did not require any correction as part of this dedupe check — the claim is accurate and already load-bearing in the vault.
Why no further primary-text research was performed
The sourcing floor (Tier 1–2 for technical-mechanism and corrected-bibliographic claims) was already met by a direct, page-numbered, page-by-page read of the primary PDF in the 2026-07-01 capture, and the venue correction is now corroborated by two independent Tier 1–2 sources (Springer's own metadata, and — new this pass — CrossRef's DOI registry). Re-reading the same 15-page scanned PDF a third time would not add new evidence beyond what two prior passes already established at the ceiling tier for these claim types. Per the operating spec's instruction that a complete, non-forced outcome is valid, this capture records the dedupe finding (plus the one incremental corroboration that was genuinely new) rather than manufacturing duplicate research on an already-closed question.