Pith Number

pith:XJ4YPCHA

pith:2013:XJ4YPCHABWFALLAUMMYWVRTL56

not attested not anchored not stored refs pending

The Post correspondence problem in groups

Alexander Ushakov, Alexei Myasnikov, Andrey Nikolaev

arxiv:1310.5246 v2 · 2013-10-19 · math.GR · cs.CC · math.CO

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{XJ4YPCHABWFALLAUMMYWVRTL56}

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	2026-05-18T01:35:33.107396Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ba798788e00d8a05ac1463316ac66befb518d08b1fb9e243d965589a0b5807f7

Aliases

arxiv: 1310.5246 · arxiv_version: 1310.5246v2 · doi: 10.48550/arxiv.1310.5246 · pith_short_12: XJ4YPCHABWFA · pith_short_16: XJ4YPCHABWFALLAU · pith_short_8: XJ4YPCHA

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/XJ4YPCHABWFALLAUMMYWVRTL56 \
  | 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: ba798788e00d8a05ac1463316ac66befb518d08b1fb9e243d965589a0b5807f7

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "ca404cbe1617e7a7746f7911a0bec675ae88dcb0395debbe658f0a17eccf447b",
    "cross_cats_sorted": [
      "cs.CC",
      "math.CO"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GR",
    "submitted_at": "2013-10-19T16:47:48Z",
    "title_canon_sha256": "b7988b86383d522a66e891104dce903656dbe627fd1cbe65aa3dd58445ff988a"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1310.5246",
    "kind": "arxiv",
    "version": 2
  }
}