Pith Number

pith:547VVVWO

pith:2015:547VVVWOLTAGLSSLIRZ5MRCXRL

not attested not anchored not stored refs pending

Algorithmic decidability of Engel's property for automaton groups

Laurent Bartholdi

arxiv:1512.01717 v1 · 2015-12-06 · cs.FL · math.GR

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{547VVVWOLTAGLSSLIRZ5MRCXRL}

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	2026-05-18T01:11:54.870867Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ef3f5ad6ce5cc065ca4b4473d644578adaa5b7f22f170ad6a05b56c96c185f98

Aliases

arxiv: 1512.01717 · arxiv_version: 1512.01717v1 · doi: 10.48550/arxiv.1512.01717 · pith_short_12: 547VVVWOLTAG · pith_short_16: 547VVVWOLTAGLSSL · pith_short_8: 547VVVWO

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/547VVVWOLTAGLSSLIRZ5MRCXRL \
  | 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: ef3f5ad6ce5cc065ca4b4473d644578adaa5b7f22f170ad6a05b56c96c185f98

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "ccb7abb0d51c25fbfc5e45d7031c28d159dfd77edb70e3a61d44ea64fe01da6b",
    "cross_cats_sorted": [
      "math.GR"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.FL",
    "submitted_at": "2015-12-06T00:44:19Z",
    "title_canon_sha256": "e017f0e7ce24378d7f56c55a4471db3423a11e3cbdd1915ca4f60cccdd7b892f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1512.01717",
    "kind": "arxiv",
    "version": 1
  }
}