Pith Number

pith:E5PEK6SY

pith:2018:E5PEK6SYBMZK7WQPUNJK4USBTH

not attested not anchored not stored refs pending

The chromatic number of the plane is at least 5

Aubrey D.N.J. de Grey

arxiv:1804.02385 v3 · 2018-04-08 · 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{E5PEK6SYBMZK7WQPUNJK4USBTH}

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	2026-05-18T00:14:33.883658Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

275e457a580b32afda0fa352ae524199cfe88510863876ae73a4c077fa81bd88

Aliases

arxiv: 1804.02385 · arxiv_version: 1804.02385v3 · doi: 10.48550/arxiv.1804.02385 · pith_short_12: E5PEK6SYBMZK · pith_short_16: E5PEK6SYBMZK7WQP · pith_short_8: E5PEK6SY

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/E5PEK6SYBMZK7WQPUNJK4USBTH \
  | 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: 275e457a580b32afda0fa352ae524199cfe88510863876ae73a4c077fa81bd88

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "5380b88a3ef03db9e89ce245276908128d1ddfc960978572a884747c9a37dc11",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2018-04-08T00:33:50Z",
    "title_canon_sha256": "90f99a9f9af8fb44ac04c7036275b30b0c59db987ea7ec0ad20cd0d4d745d57e"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1804.02385",
    "kind": "arxiv",
    "version": 3
  }
}