Pith Number

pith:56VNIR2Z

pith:2009:56VNIR2ZLKPB45HD5K4OD5LHYE

not attested not anchored not stored refs pending

Weighted Well-Covered Graphs without Cycles of Length 4, 5, 6 and 7

David Tankus, Vadim E. Levit

arxiv:0901.0858 v4 · 2009-01-07 · cs.DM · cs.CC

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{56VNIR2ZLKPB45HD5K4OD5LHYE}

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	2026-05-18T04:40:54.739485Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

efaad447595a9e1e74e3eab8e1f567c10c4896ec87fd36b5c8a78b56d08d9d38

Aliases

arxiv: 0901.0858 · arxiv_version: 0901.0858v4 · doi: 10.48550/arxiv.0901.0858 · pith_short_12: 56VNIR2ZLKPB · pith_short_16: 56VNIR2ZLKPB45HD · pith_short_8: 56VNIR2Z

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/56VNIR2ZLKPB45HD5K4OD5LHYE \
  | 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: efaad447595a9e1e74e3eab8e1f567c10c4896ec87fd36b5c8a78b56d08d9d38

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "439ad4cd5d8b382c768a3af81d0c26937e393ee4f152450d864607990750f418",
    "cross_cats_sorted": [
      "cs.CC"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.DM",
    "submitted_at": "2009-01-07T16:09:49Z",
    "title_canon_sha256": "804160f33d422454688f57d3bf29b6cf9e430f92e1aacb7f6f20cf37d8505058"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0901.0858",
    "kind": "arxiv",
    "version": 4
  }
}