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Pith Number

pith:GK55I2DZ

pith:1994:GK55I2DZEHALXRFWLBBHJOAVES
not attested not anchored not stored refs pending

Densities of ultraproducts of Boolean algebras

Sabine Koppelberg, Saharon Shelah

arxiv:math/9404226 v1 · 1994-04-15 · math.LO · math.GN

Add to your LaTeX paper
\usepackage{pith}
\pithnumber{GK55I2DZEHALXRFWLBBHJOAVES}

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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 2026-05-18T01:05:51.431292Z
Builder pith-number-builder-2026-05-17-v1
Signature Pith Ed25519 (pith-v1-2026-05) · public key
Schema pith-number/v1.0

Canonical hash

32bbd4687921c0bbc4b6584274b81524824ad24430284d49db4e221d055a0c32

Aliases

arxiv: math/9404226 · arxiv_version: math/9404226v1 · doi: 10.48550/arxiv.math/9404226 · pith_short_12: GK55I2DZEHAL · pith_short_16: GK55I2DZEHALXRFW · pith_short_8: GK55I2DZ
Agent API
Verify this Pith Number yourself
curl -sH 'Accept: application/ld+json' https://pith.science/pith/GK55I2DZEHALXRFWLBBHJOAVES \
  | 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: 32bbd4687921c0bbc4b6584274b81524824ad24430284d49db4e221d055a0c32
Canonical record JSON
{
  "metadata": {
    "abstract_canon_sha256": "a148b30b75b846777afc6ccad0c1eff52128e93a7a955574cda65e5c0ddbc545",
    "cross_cats_sorted": [
      "math.GN"
    ],
    "license": "",
    "primary_cat": "math.LO",
    "submitted_at": "1994-04-15T00:00:00Z",
    "title_canon_sha256": "799c4d6b11e302a31147ef9fb0b8cd916b951cdfa1a0d36d9f2854f473b33069"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/9404226",
    "kind": "arxiv",
    "version": 1
  }
}