Pith Number

pith:WNI2TDAP

pith:2026:WNI2TDAPZ472NIFUFMMB55CSUE

not attested not anchored not stored refs pending

Faster 3-colouring algorithm for graphs of diameter 3

Carla Groenland, Hidde Koerts, Sophie Spirkl

arxiv:2601.13072 v2 · 2026-01-19 · math.CO · cs.DM

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{WNI2TDAPZ472NIFUFMMB55CSUE}

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	2026-05-26T02:05:05.621613Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

b351a98c0fcf3fa6a0b42b181ef452a108a1dccc3d67c2641517d43bc17346dc

Aliases

arxiv: 2601.13072 · arxiv_version: 2601.13072v2 · doi: 10.48550/arxiv.2601.13072 · pith_short_12: WNI2TDAPZ472 · pith_short_16: WNI2TDAPZ472NIFU · pith_short_8: WNI2TDAP

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/WNI2TDAPZ472NIFUFMMB55CSUE \
  | 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: b351a98c0fcf3fa6a0b42b181ef452a108a1dccc3d67c2641517d43bc17346dc

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "5f969a68b338fcf15529fd7ea3cfc3069fafca1f409c019a308904844ab42673",
    "cross_cats_sorted": [
      "cs.DM"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2026-01-19T14:05:52Z",
    "title_canon_sha256": "1f351ec52625f456f2b39d2c95d135a5074adf42d3ab37959b574948c8fdf4ce"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2601.13072",
    "kind": "arxiv",
    "version": 2
  }
}