Pith Number

pith:O54TFCF7

pith:2015:O54TFCF7XJ5EQO4PTLKKR5A45H

not attested not anchored not stored refs pending

Robust preconditioners for PDE-constrained optimization with limited observations

Bj{\o}rn Fredrik Nielsen, Kent-Andr\'e Mardal, Magne Nordaas

arxiv:1506.06494 v1 · 2015-06-22 · math.OC · math.AP

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{O54TFCF7XJ5EQO4PTLKKR5A45H}

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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	2026-05-18T01:41:45.068229Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

77793288bfba7a483b8f9ad4a8f41ce9e68faf44858687a2e4d8b3881a915368

Aliases

arxiv: 1506.06494 · arxiv_version: 1506.06494v1 · doi: 10.48550/arxiv.1506.06494 · pith_short_12: O54TFCF7XJ5E · pith_short_16: O54TFCF7XJ5EQO4P · pith_short_8: O54TFCF7

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/O54TFCF7XJ5EQO4PTLKKR5A45H \
  | 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: 77793288bfba7a483b8f9ad4a8f41ce9e68faf44858687a2e4d8b3881a915368

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "0c9266ec36108adfd1feb03b2fe2d78c69008ccf932923acb0e6b84f622925f7",
    "cross_cats_sorted": [
      "math.AP"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.OC",
    "submitted_at": "2015-06-22T07:52:38Z",
    "title_canon_sha256": "636588bc3ef091658c0ee20cf997ef1d530ff28680c9a56cddddbef06798f43b"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1506.06494",
    "kind": "arxiv",
    "version": 1
  }
}