Pith Number

pith:HGG2KA75

pith:2013:HGG2KA756Q7GKMYXESXW663USR

not attested not anchored not stored refs pending

The separation problem for regular languages by piecewise testable languages

Lorijn van Rooijen, Marc Zeitoun

arxiv:1303.2143 v1 · 2013-03-08 · cs.FL

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{HGG2KA756Q7GKMYXESXW663USR}

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	2026-05-18T03:31:19.943573Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

398da503fdf43e65331724af6f7b74945aa0ae43437328a3c7d0448d9a46226d

Aliases

arxiv: 1303.2143 · arxiv_version: 1303.2143v1 · doi: 10.48550/arxiv.1303.2143 · pith_short_12: HGG2KA756Q7G · pith_short_16: HGG2KA756Q7GKMYX · pith_short_8: HGG2KA75

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/HGG2KA756Q7GKMYXESXW663USR \
  | 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: 398da503fdf43e65331724af6f7b74945aa0ae43437328a3c7d0448d9a46226d

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "4ec89ddf6e55b47ec17b9dd1e3bfb758852686046b31f2a608ef6e2363ca3449",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.FL",
    "submitted_at": "2013-03-08T23:01:05Z",
    "title_canon_sha256": "2ed86931b9dbf4b0882fbecc96183f77610dd0db5c6a017eebc89d1e53748e4c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1303.2143",
    "kind": "arxiv",
    "version": 1
  }
}