Pith Number

pith:CBCXNYCN

pith:2017:CBCXNYCNVDFEMNVKXCVVZ25VWW

not attested not anchored not stored refs pending

A note on preconditioning weighted linear least squares, with consequences for weakly-constrained variational data assimilation

Ehouarn Simon, Philippe L. Toint, Selime G\"urol, Serge Gratton

arxiv:1709.09031 v1 · 2017-09-26 · math.NA · cs.NA · math.OC

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{CBCXNYCNVDFEMNVKXCVVZ25VWW}

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	2026-06-04T19:11:01.762471Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

104576e04da8ca4636aab8ab5cebb5b583e00ac3381afc22b1d91e4b6ef1b6d8

Aliases

arxiv: 1709.09031 · arxiv_version: 1709.09031v1 · doi: 10.48550/arxiv.1709.09031 · pith_short_12: CBCXNYCNVDFE · pith_short_16: CBCXNYCNVDFEMNVK · pith_short_8: CBCXNYCN

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/CBCXNYCNVDFEMNVKXCVVZ25VWW \
  | 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: 104576e04da8ca4636aab8ab5cebb5b583e00ac3381afc22b1d91e4b6ef1b6d8

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "60772baa665c9dd229abbe2290d2ee18a90c7f4b1d1446732bf6bd1f35a8d6fb",
    "cross_cats_sorted": [
      "cs.NA",
      "math.OC"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.NA",
    "submitted_at": "2017-09-26T14:16:55Z",
    "title_canon_sha256": "05c68ced434d0f501f342adb4b91e59703f81b84e636279e400b77646a672d02"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1709.09031",
    "kind": "arxiv",
    "version": 1
  }
}