Pith Number

pith:7HHYCSIS

pith:2012:7HHYCSISORMDRNAUDGDEPWHZPM

not attested not anchored not stored refs pending

An effective characterization of the alternation hierarchy in two-variable logic

Andreas Krebs, Howard Straubing

arxiv:1205.4802 v1 · 2012-05-22 · cs.LO

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{7HHYCSISORMDRNAUDGDEPWHZPM}

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	2026-05-18T03:55:11.622106Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

f9cf814912745838b414198647d8f97b2e46f97ddf2ce1b3bd54f379f8ac8648

Aliases

arxiv: 1205.4802 · arxiv_version: 1205.4802v1 · doi: 10.48550/arxiv.1205.4802 · pith_short_12: 7HHYCSISORMD · pith_short_16: 7HHYCSISORMDRNAU · pith_short_8: 7HHYCSIS

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/7HHYCSISORMDRNAUDGDEPWHZPM \
  | 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: f9cf814912745838b414198647d8f97b2e46f97ddf2ce1b3bd54f379f8ac8648

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "235efdc8e2cb6388696d4d56cc3280cf4d8e7e2be38910f63d4a863895e62687",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.LO",
    "submitted_at": "2012-05-22T05:16:30Z",
    "title_canon_sha256": "7e6eb443c75c162d2fe1a110214825c3f524a304f0a928d78e76b728875bae35"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1205.4802",
    "kind": "arxiv",
    "version": 1
  }
}