Pith Number

pith:VEJ4I5SI

pith:2010:VEJ4I5SIS5EUBQ7EFOYSYJDERY

not attested not anchored not stored refs pending

Bockstein Closed 2-Group Extensions and Cohomology of Quadratic Maps

Ergun Yalcin, Jonathan Pakianathan

arxiv:1007.2390 v2 · 2010-07-14 · math.AT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{VEJ4I5SIS5EUBQ7EFOYSYJDERY}

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	2026-05-18T03:56:58.367325Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

a913c47648974940c3e42bb12c24648e074cb8edb811bc9bca5556bf55d78063

Aliases

arxiv: 1007.2390 · arxiv_version: 1007.2390v2 · doi: 10.48550/arxiv.1007.2390 · pith_short_12: VEJ4I5SIS5EU · pith_short_16: VEJ4I5SIS5EUBQ7E · pith_short_8: VEJ4I5SI

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/VEJ4I5SIS5EUBQ7EFOYSYJDERY \
  | 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: a913c47648974940c3e42bb12c24648e074cb8edb811bc9bca5556bf55d78063

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "513f80c62acce630f75b2f33a0a6ad24f539f1afe9563f192121b4c1410809b5",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AT",
    "submitted_at": "2010-07-14T18:22:44Z",
    "title_canon_sha256": "7937248ddd43da2d83e547cfc1126b196750fdf33333144ea51a87a67cb2059f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1007.2390",
    "kind": "arxiv",
    "version": 2
  }
}