Pith Number

pith:K7IRW4EE

pith:1999:K7IRW4EEF5PKZX5QL7XCH36CRG

not attested not anchored not stored refs pending

Permanents, Pfaffian orientations, and even directed circuits

Neil Robertson, P. D. Seymour, Robin Thomas

arxiv:math/9911268 v1 · 1999-11-01 · 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{K7IRW4EEF5PKZX5QL7XCH36CRG}

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	2026-05-18T01:05:32.317120Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

57d11b70842f5eacdfb05fee23efc289ba4a0e0d98c78786636f0cb21836b723

Aliases

arxiv: math/9911268 · arxiv_version: math/9911268v1 · doi: 10.48550/arxiv.math/9911268 · pith_short_12: K7IRW4EEF5PK · pith_short_16: K7IRW4EEF5PKZX5Q · pith_short_8: K7IRW4EE

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/K7IRW4EEF5PKZX5QL7XCH36CRG \
  | 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: 57d11b70842f5eacdfb05fee23efc289ba4a0e0d98c78786636f0cb21836b723

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "0b0f8a7c610a92aef033d627459c80ca588002819130c1add6043b49a76da895",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "math.CO",
    "submitted_at": "1999-11-01T00:00:00Z",
    "title_canon_sha256": "bc9cfc690f1da5c562de4113777b67ca128e3773351de57ff02b36e18fe5d701"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/9911268",
    "kind": "arxiv",
    "version": 1
  }
}