Pith Number

pith:YIN2ZBEQ

pith:2015:YIN2ZBEQ2W7FPDNC5KTJEP7EJU

not attested not anchored not stored refs pending

Assembling homology classes in automorphism groups of free groups

Allen Hatcher, James Conant, Karen Vogtmann, Martin Kassabov

arxiv:1501.02351 v4 · 2015-01-10 · math.AT · math.GR · math.QA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{YIN2ZBEQ2W7FPDNC5KTJEP7EJU}

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	2026-05-18T00:50:12.608723Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

c21bac8490d5be578da2eaa6923fe44d2aafdd99311a4c21e5705c5e75bfccaa

Aliases

arxiv: 1501.02351 · arxiv_version: 1501.02351v4 · doi: 10.48550/arxiv.1501.02351 · pith_short_12: YIN2ZBEQ2W7F · pith_short_16: YIN2ZBEQ2W7FPDNC · pith_short_8: YIN2ZBEQ

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/YIN2ZBEQ2W7FPDNC5KTJEP7EJU \
  | 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: c21bac8490d5be578da2eaa6923fe44d2aafdd99311a4c21e5705c5e75bfccaa

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "08fa4887beb23066268dbf5dc0ac43f48cda2ed19f6593a59d3a05f64b8b87c5",
    "cross_cats_sorted": [
      "math.GR",
      "math.QA"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AT",
    "submitted_at": "2015-01-10T13:03:04Z",
    "title_canon_sha256": "9c5ef2231aaae42863c1d31155645fdf0f053c3bd79a5f253ca4964fa8bfb738"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1501.02351",
    "kind": "arxiv",
    "version": 4
  }
}