Pith Number

pith:PYVM7TMF

pith:1992:PYVM7TMFIIL6IKPMDTSARM3LCR

not attested not anchored not stored refs pending

A combinatorial formula for the Pontrjagin classes

Israel M. Gelfand, Robert D. MacPherson

arxiv:math/9204231 v1 · 1992-04-01 · math.AT · math.GT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{PYVM7TMFIIL6IKPMDTSARM3LCR}

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	2026-05-18T01:05:52.828083Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

7e2acfcd854217e429ec1ce408b36b147b0adebdd930bf958c8e8582a30c3f5b

Aliases

arxiv: math/9204231 · arxiv_version: math/9204231v1 · doi: 10.48550/arxiv.math/9204231 · pith_short_12: PYVM7TMFIIL6 · pith_short_16: PYVM7TMFIIL6IKPM · pith_short_8: PYVM7TMF

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/PYVM7TMFIIL6IKPMDTSARM3LCR \
  | 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: 7e2acfcd854217e429ec1ce408b36b147b0adebdd930bf958c8e8582a30c3f5b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "24f39e294470ac572de7b9030f3dfd69bedf034f3acda37ea4145db5e88ef6c5",
    "cross_cats_sorted": [
      "math.GT"
    ],
    "license": "",
    "primary_cat": "math.AT",
    "submitted_at": "1992-04-01T00:00:00Z",
    "title_canon_sha256": "aaf9a606a29a30bce0be91400d678d44202e95442a49de8e66c4af160e30ba51"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/9204231",
    "kind": "arxiv",
    "version": 1
  }
}