Pith Number

pith:LP2KXNTC

pith:2013:LP2KXNTCRSU64ZH7PNDDCZEV2F

not attested not anchored not stored refs pending

Free actions of free groups on countable structures and property (T)

David M. Evans, Todor Tsankov

arxiv:1312.5140 v2 · 2013-12-18 · math.GR · math.LO

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

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	2026-05-18T01:34:13.648190Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

5bf4abb6628ca9ee64ff7b46316495d16a2fe8297a10407b09a281f48d044478

Aliases

arxiv: 1312.5140 · arxiv_version: 1312.5140v2 · doi: 10.48550/arxiv.1312.5140 · pith_short_12: LP2KXNTCRSU6 · pith_short_16: LP2KXNTCRSU64ZH7 · pith_short_8: LP2KXNTC

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/LP2KXNTCRSU64ZH7PNDDCZEV2F \
  | 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: 5bf4abb6628ca9ee64ff7b46316495d16a2fe8297a10407b09a281f48d044478

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "f0ed01ff78659dbe206505aa8d93941bd377c14475a1210673fd33196ac0fb78",
    "cross_cats_sorted": [
      "math.LO"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GR",
    "submitted_at": "2013-12-18T13:56:26Z",
    "title_canon_sha256": "03b8e917af80f3695b94f3715524d5dc28f49d0df7e2d0c26488e9d2309583fa"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1312.5140",
    "kind": "arxiv",
    "version": 2
  }
}