Pith Number

pith:4FYPSDTJ

pith:2018:4FYPSDTJX2WOVBNVCVTNTCXSFA

not attested not anchored not stored refs pending

Short directed cycles in bipartite digraphs

Paul Seymour, Sophie Spirkl

arxiv:1809.08324 v2 · 2018-09-21 · 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{4FYPSDTJX2WOVBNVCVTNTCXSFA}

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	2026-05-17T23:39:41.635539Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e170f90e69beacea85b51566d98af22811d48de930e1b0bd96797b78d41b854a

Aliases

arxiv: 1809.08324 · arxiv_version: 1809.08324v2 · doi: 10.48550/arxiv.1809.08324 · pith_short_12: 4FYPSDTJX2WO · pith_short_16: 4FYPSDTJX2WOVBNV · pith_short_8: 4FYPSDTJ

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/4FYPSDTJX2WOVBNVCVTNTCXSFA \
  | 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: e170f90e69beacea85b51566d98af22811d48de930e1b0bd96797b78d41b854a

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a242f574af9f773e68f59017ea48d53887a19e8014c5bab749279938441bab86",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2018-09-21T21:43:15Z",
    "title_canon_sha256": "1c77f2b6ee5bc313eea413c2f7b8cdfbf8327b514d388e881ab435bf1e0b09bc"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1809.08324",
    "kind": "arxiv",
    "version": 2
  }
}