Pith Number

pith:4CYSDUDB

pith:2013:4CYSDUDBBFNGRXVXEIYLWUOJNX

not attested not anchored not stored refs pending

Some effectivity questions for plane Cremona transformations

N.I. Shepherd-Barron

arxiv:1311.6608 v5 · 2013-11-26 · math.AG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{4CYSDUDBBFNGRXVXEIYLWUOJNX}

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	2026-05-17T23:48:41.228285Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e0b121d061095a68deb72230bb51c96dcd18e54234aa4405102b993a6b4dcc78

Aliases

arxiv: 1311.6608 · arxiv_version: 1311.6608v5 · doi: 10.48550/arxiv.1311.6608 · pith_short_12: 4CYSDUDBBFNG · pith_short_16: 4CYSDUDBBFNGRXVX · pith_short_8: 4CYSDUDB

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/4CYSDUDBBFNGRXVXEIYLWUOJNX \
  | 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: e0b121d061095a68deb72230bb51c96dcd18e54234aa4405102b993a6b4dcc78

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "fc1fb06a0fc4021d70e4efd8da1bad992733c36828576017b0aefef2aa523e83",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2013-11-26T10:08:33Z",
    "title_canon_sha256": "2209e08a75b21d7151c0c1664109c9ff31a8034d051da84f9ddbda95a7214b63"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1311.6608",
    "kind": "arxiv",
    "version": 5
  }
}