Pith Number

pith:KDDJQYHI

pith:2009:KDDJQYHIEXOPER7W64GXVSQUJZ

not attested not anchored not stored refs pending

A geometric construction of Mathon's perp-system from four lines of PG(5,3)

Frank De Clerck, John Bamberg

arxiv:0910.2830 v2 · 2009-10-15 · math.CO · 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{KDDJQYHIEXOPER7W64GXVSQUJZ}

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	2026-05-18T03:52:51.684176Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

50c69860e825dcf247f6f70d7aca144e5cdaa8d21d4cf945543aad352f55d174

Aliases

arxiv: 0910.2830 · arxiv_version: 0910.2830v2 · doi: 10.48550/arxiv.0910.2830 · pith_short_12: KDDJQYHIEXOP · pith_short_16: KDDJQYHIEXOPER7W · pith_short_8: KDDJQYHI

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/KDDJQYHIEXOPER7W64GXVSQUJZ \
  | 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: 50c69860e825dcf247f6f70d7aca144e5cdaa8d21d4cf945543aad352f55d174

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "bab00272f4d425079dc761201d769a6651290620526d9d86331004709169ea53",
    "cross_cats_sorted": [
      "math.GR"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2009-10-15T10:21:08Z",
    "title_canon_sha256": "b6680311a02c2edd05e150a1a29547c5353979f894b0610be3b94a5042a97a67"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0910.2830",
    "kind": "arxiv",
    "version": 2
  }
}