Pith Number

pith:OPSNZ3IY

pith:2012:OPSNZ3IY5F2GUAMTW4COPOK5TT

not attested not anchored not stored refs pending

On the minimal feedback arc set of m-free Digraphs

Hao Liang, Jun-Ming Xu

arxiv:1204.4516 v1 · 2012-04-20 · 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{OPSNZ3IY5F2GUAMTW4COPOK5TT}

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	2026-05-18T03:57:26.337728Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

73e4dced18e9746a0193b704e7b95d9cc7770134a3f2f7f2c2ebf2c6632d366e

Aliases

arxiv: 1204.4516 · arxiv_version: 1204.4516v1 · doi: 10.48550/arxiv.1204.4516 · pith_short_12: OPSNZ3IY5F2G · pith_short_16: OPSNZ3IY5F2GUAMT · pith_short_8: OPSNZ3IY

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/OPSNZ3IY5F2GUAMTW4COPOK5TT \
  | 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: 73e4dced18e9746a0193b704e7b95d9cc7770134a3f2f7f2c2ebf2c6632d366e

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a4cd9a7b74cff37a7ebfc9f89a1dcfd9cc34b15776e564cd04d4ada8802c77f2",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2012-04-20T02:05:00Z",
    "title_canon_sha256": "c4dd57ef8e4507e23ff52906426328fc1f424cd9341b3be8f16651b864a2a832"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1204.4516",
    "kind": "arxiv",
    "version": 1
  }
}