Pith Number

pith:2QKB2MCM

pith:2011:2QKB2MCMDVE64QF6T5IRR3TMAF

not attested not anchored not stored refs pending

Decidability of the HD0L ultimate periodicity problem

Fabien Durand (LAMFA)

arxiv:1111.3268 v3 · 2011-11-14 · math.CO · 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{2QKB2MCMDVE64QF6T5IRR3TMAF}

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	2026-05-18T03:37:29.067591Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

d4141d304c1d49ee40be9f5118ee6c01522b3a0a343a90bafda62fb0c58572cc

Aliases

arxiv: 1111.3268 · arxiv_version: 1111.3268v3 · doi: 10.48550/arxiv.1111.3268 · pith_short_12: 2QKB2MCMDVE6 · pith_short_16: 2QKB2MCMDVE64QF6 · pith_short_8: 2QKB2MCM

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/2QKB2MCMDVE64QF6T5IRR3TMAF \
  | 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: d4141d304c1d49ee40be9f5118ee6c01522b3a0a343a90bafda62fb0c58572cc

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "7fbff8b1e4817c97774986ad62b263267c9ce958cd95016b4df3816eaeca8dca",
    "cross_cats_sorted": [
      "cs.FL"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2011-11-14T16:21:50Z",
    "title_canon_sha256": "19531f51ffd452fe245d23b9bd47cd94a682dbfceb6c58209cb0f1fca10b18ff"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1111.3268",
    "kind": "arxiv",
    "version": 3
  }
}