Pith Number

pith:HMQ7DQ7T

pith:2012:HMQ7DQ7TNW32Q7RKFN3IHAO5Y2

not attested not anchored not stored refs pending

Visibly pushdown automata on trees: universality and u-universality

Marc Ducobu, Olivier Gauwin, V\'eronique Bruy\`ere

arxiv:1205.2841 v1 · 2012-05-13 · cs.FL

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{HMQ7DQ7TNW32Q7RKFN3IHAO5Y2}

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	2026-05-18T03:55:45.884594Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

3b21f1c3f36db7a87e2a2b768381ddc69d4712f8630d6c483e2b7128faa2e85b

Aliases

arxiv: 1205.2841 · arxiv_version: 1205.2841v1 · doi: 10.48550/arxiv.1205.2841 · pith_short_12: HMQ7DQ7TNW32 · pith_short_16: HMQ7DQ7TNW32Q7RK · pith_short_8: HMQ7DQ7T

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/HMQ7DQ7TNW32Q7RKFN3IHAO5Y2 \
  | 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: 3b21f1c3f36db7a87e2a2b768381ddc69d4712f8630d6c483e2b7128faa2e85b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "37e960410845b3447c8a06f83ba522425e6974b4f797227fdae156a0b0872a5d",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.FL",
    "submitted_at": "2012-05-13T07:53:00Z",
    "title_canon_sha256": "b0b8e5ae774ef0fed80bc336882c8e0ad2498d6e72ed92d19bb5ac7c8f3393f1"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1205.2841",
    "kind": "arxiv",
    "version": 1
  }
}