Pith Number

pith:RQ5RJIZ5

pith:1999:RQ5RJIZ5FAZAV6E76O472S2YLQ

not attested not anchored not stored refs pending

Compacting the Penn Treebank Grammar

Alexander Krotov, Mark Hepple, Robert Gaizauskas, UK), University of Sheffield, Yorick Wilks (Department of Computer Science

arxiv:cs/9902001 v1 · 1999-01-31 · cs.CL

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{RQ5RJIZ5FAZAV6E76O472S2YLQ}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-07-04T14:25:09.349254Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

8c3b14a33d28320af89ff3b9fd4b585c2d93ae1c2024fe51bd417b3bd7309fae

Aliases

arxiv: cs/9902001 · arxiv_version: cs/9902001v1 · doi: 10.48550/arxiv.cs/9902001 · pith_short_12: RQ5RJIZ5FAZA · pith_short_16: RQ5RJIZ5FAZAV6E7 · pith_short_8: RQ5RJIZ5

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/RQ5RJIZ5FAZAV6E76O472S2YLQ \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 8c3b14a33d28320af89ff3b9fd4b585c2d93ae1c2024fe51bd417b3bd7309fae

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "502de2d444c9a915a45cb15c4bf54494fdbcdddcc83da69d47e63dd4da080a8e",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "cs.CL",
    "submitted_at": "1999-01-31T18:57:45Z",
    "title_canon_sha256": "133e7930ef3852e99c44b4a6b978e7361231c0eef917f97ddbd4a563e09aacc3"
  },
  "schema_version": "1.0",
  "source": {
    "id": "cs/9902001",
    "kind": "arxiv",
    "version": 1
  }
}