Pith Number

pith:U7GXFNIA

pith:2012:U7GXFNIA3J6JE4NYI5TLML44ZH

not attested not anchored not stored refs pending

The mate-in-n problem of infinite chess is decidable

Dan Brumleve, Joel David Hamkins, Philipp Schlicht

arxiv:1201.5597 v4 · 2012-01-26 · math.LO · cs.LO

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{U7GXFNIA3J6JE4NYI5TLML44ZH}

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	2026-05-18T03:55:35.345138Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

a7cd72b500da7c9271b84766b62f9cc9c227a0d034499fed618a6cdf9c726453

Aliases

arxiv: 1201.5597 · arxiv_version: 1201.5597v4 · doi: 10.48550/arxiv.1201.5597 · pith_short_12: U7GXFNIA3J6J · pith_short_16: U7GXFNIA3J6JE4NY · pith_short_8: U7GXFNIA

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/U7GXFNIA3J6JE4NYI5TLML44ZH \
  | 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: a7cd72b500da7c9271b84766b62f9cc9c227a0d034499fed618a6cdf9c726453

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "ea836186bfb93f361d40a8e5e6ed99e6d39759d54876716c2d7af7e7bd0c6661",
    "cross_cats_sorted": [
      "cs.LO"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.LO",
    "submitted_at": "2012-01-26T18:26:57Z",
    "title_canon_sha256": "eb82a8f77d693529dbafd8e49bb44ad19223a7cd91c5f25f47775e188e512738"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1201.5597",
    "kind": "arxiv",
    "version": 4
  }
}