Pith Number

pith:IES3F3RQ

pith:2019:IES3F3RQSPJCK6UPQXWHACL4FG

not attested not anchored not stored refs pending

Link Crossing Number is NP-hard

Arnaud de Mesmay, Eric Sedgwick, Marcus Schaefer

arxiv:1908.04073 v1 · 2019-08-12 · cs.CG · math.GT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{IES3F3RQSPJCK6UPQXWHACL4FG}

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	2026-07-04T23:53:20.401546Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

4125b2ee3093d2257a8f85ec70097c2998c3043699b461132ed16c7f30fdf49a

Aliases

arxiv: 1908.04073 · arxiv_version: 1908.04073v1 · doi: 10.48550/arxiv.1908.04073 · pith_short_12: IES3F3RQSPJC · pith_short_16: IES3F3RQSPJCK6UP · pith_short_8: IES3F3RQ

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/IES3F3RQSPJCK6UPQXWHACL4FG \
  | 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: 4125b2ee3093d2257a8f85ec70097c2998c3043699b461132ed16c7f30fdf49a

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "ef4e910691ce7f52a0b08f277e94481aaeaf7c03a1f152e2e26ad2f13c9a4fb0",
    "cross_cats_sorted": [
      "math.GT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.CG",
    "submitted_at": "2019-08-12T10:04:04Z",
    "title_canon_sha256": "0aa700b698f1c746b628810fe215db601dd18fcc862243d2645fe3e71ac9f972"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1908.04073",
    "kind": "arxiv",
    "version": 1
  }
}