Pith Number

pith:R4QMT35G

pith:2026:R4QMT35G5S7JJFH4B25GVYS3KM

not attested not anchored not stored refs pending

A new group in the Riordan family of matrix groups: the Sprugnoli group

Paul Barry

arxiv:2605.16633 v1 · 2026-05-15 · math.CO

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{R4QMT35G5S7JJFH4B25GVYS3KM}

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	2026-05-20T00:02:33.473596Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

8f20c9efa6ecbe9494fc0eba6ae25b530114c8ff31585763f8169b048261a76b

Aliases

arxiv: 2605.16633 · arxiv_version: 2605.16633v1 · doi: 10.48550/arxiv.2605.16633 · pith_short_12: R4QMT35G5S7J · pith_short_16: R4QMT35G5S7JJFH4 · pith_short_8: R4QMT35G

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/R4QMT35G5S7JJFH4B25GVYS3KM \
  | 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: 8f20c9efa6ecbe9494fc0eba6ae25b530114c8ff31585763f8169b048261a76b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "297676c60aa746a927df0c75aeda6ad0afaac745ca1efad394734d5bec240166",
    "cross_cats_sorted": [],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "math.CO",
    "submitted_at": "2026-05-15T21:04:08Z",
    "title_canon_sha256": "31fe28c553f04f37f8bf9417dd160f7d982e5c29a9d880ff18e56afaff5d6a23"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2605.16633",
    "kind": "arxiv",
    "version": 1
  }
}