Pith Number

pith:4PBCLAFX

pith:2019:4PBCLAFXRDKOC4Y2UHW23EDYPL

not attested not anchored not stored refs pending

Positive answers to Koch's problem in special cases

Alex Ravsky, Igor Guran, Oleg Gutik, Serhii Bardyla, Taras Banakh

arxiv:1902.08895 v1 · 2019-02-24 · math.GR

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{4PBCLAFXRDKOC4Y2UHW23EDYPL}

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	2026-05-17T23:52:49.539028Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e3c22580b788d4e1731aa1edad90787af7daafb9458beafe32bf151c7642aa5e

Aliases

arxiv: 1902.08895 · arxiv_version: 1902.08895v1 · doi: 10.48550/arxiv.1902.08895 · pith_short_12: 4PBCLAFXRDKO · pith_short_16: 4PBCLAFXRDKOC4Y2 · pith_short_8: 4PBCLAFX

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/4PBCLAFXRDKOC4Y2UHW23EDYPL \
  | 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: e3c22580b788d4e1731aa1edad90787af7daafb9458beafe32bf151c7642aa5e

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "fd17177b4c1ccb266b95826257c4b215182b5a79da95bd80f5c85a332e49d9e7",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GR",
    "submitted_at": "2019-02-24T05:01:53Z",
    "title_canon_sha256": "ba65b00ef057c8a6941843986a944e6f629bb8de54d858f5751451e17d33e505"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1902.08895",
    "kind": "arxiv",
    "version": 1
  }
}