Pith Number

pith:PHWNU6QD

pith:2013:PHWNU6QDLH56FE5F6WVEYBV6I5

not attested not anchored not stored refs pending

A variation on Heawood list-coloring for graphs on surfaces

Joan P. Hutchinson

arxiv:1302.7055 v2 · 2013-02-28 · 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{PHWNU6QDLH56FE5F6WVEYBV6I5}

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	2026-05-18T03:25:15.841265Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

79ecda7a0359fbe293a5f5aa4c06be475c71f7391779b90068dc232629874be4

Aliases

arxiv: 1302.7055 · arxiv_version: 1302.7055v2 · doi: 10.48550/arxiv.1302.7055 · pith_short_12: PHWNU6QDLH56 · pith_short_16: PHWNU6QDLH56FE5F · pith_short_8: PHWNU6QD

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/PHWNU6QDLH56FE5F6WVEYBV6I5 \
  | 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: 79ecda7a0359fbe293a5f5aa4c06be475c71f7391779b90068dc232629874be4

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "8cb9d39065adc47e8612e382b61c7fe765a4482a0eb814a5184440bb571ecaf8",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2013-02-28T02:06:06Z",
    "title_canon_sha256": "ec279bcb236d47f41abcd14734ca0547a45a72c2fe08114cc05cb1c3f66c237e"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1302.7055",
    "kind": "arxiv",
    "version": 2
  }
}