Pith Number

pith:4BYMFIA6

pith:2026:4BYMFIA6KC5U42L5J5ZQRIDV2E

not attested not anchored not stored refs pending

Constrained Variable Projection for Structured Problems

Emanuele Zangrando, Francesco Rinaldi, Francesco Tudisco, Sara Venturini

arxiv:2606.23939 v1 · 2026-06-22 · math.OC · cs.LG · cs.NA · math.NA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{4BYMFIA6KC5U42L5J5ZQRIDV2E}

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	2026-06-24T00:14:30.861435Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e070c2a01e50bb4e697d4f7308a075d10992d54c81ef087fd2cb8cb1b7643a64

Aliases

arxiv: 2606.23939 · arxiv_version: 2606.23939v1 · doi: 10.48550/arxiv.2606.23939 · pith_short_12: 4BYMFIA6KC5U · pith_short_16: 4BYMFIA6KC5U42L5 · pith_short_8: 4BYMFIA6

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/4BYMFIA6KC5U42L5J5ZQRIDV2E \
  | 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: e070c2a01e50bb4e697d4f7308a075d10992d54c81ef087fd2cb8cb1b7643a64

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a22320dfb4831a1e54475c78bb05b12582e271785d26e7397234dee6e08e5acd",
    "cross_cats_sorted": [
      "cs.LG",
      "cs.NA",
      "math.NA"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "math.OC",
    "submitted_at": "2026-06-22T21:00:35Z",
    "title_canon_sha256": "8d8033eb22b8d20b4c75688696b933c04fbd7208f5c58c19d945863e94e6fad8"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2606.23939",
    "kind": "arxiv",
    "version": 1
  }
}