Pith Number

pith:QFQ5E2NQ

pith:2008:QFQ5E2NQTY5GBM7SGY4N5SPTC2

not attested not anchored not stored refs pending

List Colouring Squares of Planar Graphs

Bruce Reed, Colin McDiarmid, Fr\'ed\'eric Havet, Jan van den Heuvel

arxiv:0807.3233 v2 · 2008-07-21 · 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{QFQ5E2NQTY5GBM7SGY4N5SPTC2}

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.

Cited by

2 papers in Pith

Coloring, List Coloring, and Painting Squares of Graphs (and other related problems)

Coloring powers of random graphs

Receipt and verification

First computed	2026-05-18T00:44:34.080812Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

8161d269b09e3a60b3f23638dec9f3169a3ce1de9cae7808e9abefc9f451815a

Aliases

arxiv: 0807.3233 · arxiv_version: 0807.3233v2 · doi: 10.48550/arxiv.0807.3233 · pith_short_12: QFQ5E2NQTY5G · pith_short_16: QFQ5E2NQTY5GBM7S · pith_short_8: QFQ5E2NQ

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/QFQ5E2NQTY5GBM7SGY4N5SPTC2 \
  | 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: 8161d269b09e3a60b3f23638dec9f3169a3ce1de9cae7808e9abefc9f451815a

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "8d84f7d3a3d6cc2f76d45f3820d6f8e6c9dc48acc6b27c9c67c76a68f539e652",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2008-07-21T10:39:56Z",
    "title_canon_sha256": "21e22d08b5a2e5f8863c0ac1f394985d58e039d208182e89dba03ecd2270d007"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0807.3233",
    "kind": "arxiv",
    "version": 2
  }
}