Pith Number

pith:EA6VFJVT

pith:2000:EA6VFJVTMT6FU3I4MHVC2MWBHM

not attested not anchored not stored refs pending

The surjectivity problem for one-generator,, one-relator extensions of torsion-free groups

Colin Rourke, Marshall M Cohen

arxiv:math/0009101 v2 · 2000-09-10 · math.GR · math.GT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{EA6VFJVTMT6FU3I4MHVC2MWBHM}

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	2026-05-18T02:38:00.949631Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

203d52a6b364fc5a6d1c61ea2d32c13b25d2b35bcf7993c0d3c7c4db92f3f41d

Aliases

arxiv: math/0009101 · arxiv_version: math/0009101v2 · doi: 10.48550/arxiv.math/0009101 · pith_short_12: EA6VFJVTMT6F · pith_short_16: EA6VFJVTMT6FU3I4 · pith_short_8: EA6VFJVT

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/EA6VFJVTMT6FU3I4MHVC2MWBHM \
  | 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: 203d52a6b364fc5a6d1c61ea2d32c13b25d2b35bcf7993c0d3c7c4db92f3f41d

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "9e2c1687535fad2701c8ba73db497ce35d99b1a6d080bf640bf179e7bb1bcd37",
    "cross_cats_sorted": [
      "math.GT"
    ],
    "license": "",
    "primary_cat": "math.GR",
    "submitted_at": "2000-09-10T20:05:46Z",
    "title_canon_sha256": "7592f7bf8e677cd2b082cbdf6248da7b3a3cbaf1b1facb530e61094d03714fc3"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/0009101",
    "kind": "arxiv",
    "version": 2
  }
}