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Integer sequencesoeis.org search (JSON)

OEIS

The On-Line Encyclopedia of Integer Sequences (OEIS) is the reference database of integer sequences, run by the OEIS Foundation. Through ScholarMuse an agent can send the first terms of a sequence, an A-number such as A000045, or keywords, and get the matching entries with their A-number, name, first terms, formulas and keywords.

ScholarMuse tools: lookup_integer_sequence. Each successful call uses credits.

Use in my agent

Ask your agent

Which sequence starts 1, 1, 2, 5, 14, 42, 132?
What is OEIS A000045, and what formulas does it list?
My program counts 1, 2, 5, 15, 52, 203 set partitions. Is this a known sequence?

What your agent gets back

Every record carries id, source, title, url, license, attribution and retrievedAt. The fields below are the data that comes from OEIS.

lookup_integer_sequence

One record per matching sequence, best match first. Terms are returned as strings because they can be larger than a normal integer.

aNumber
OEIS A-number, e.g. A000045
name
Name of the sequence
firstTerms
Up to the first 30 terms
termCount
Number of terms the OEIS entry lists
offset
Index of the first term
formulas
Up to three formula lines
keywords
OEIS keywords such as nonn or easy
author
Author of the entry
citedBySequences
How many other OEIS entries refer to it
lastModified
When the entry was last changed

What it covers

  • Integer sequences in the OEIS, found by their first terms, by A-number or by keywords.
  • For each match: name, first terms, offset, formulas, keywords, author and the link to the OEIS entry.

Limits

  • At most 10 sequences per call (5 by default).
  • Only the first 30 terms and the first three formula lines are returned, and each formula is cut at 400 characters.
  • Comments, references, links, program code and the full term files of an entry are not returned; open the entry link for those.
  • Very broad keyword searches return nothing, because the OEIS gives no results when too many sequences match.

How ScholarMuse reaches OEIS

The connector calls the search endpoint on oeis.org with fmt=json. An A-number is sent as an id: query; terms and keywords are sent as typed. No API key is sent.

Responses are cached for up to 7 days, so recent edits to an OEIS entry can take a week to appear.

API key: the upstream API can be called without one, so you do not add one.

Licence and attribution

Licence: CC BY-SA 4.0

The On-Line Encyclopedia of Integer Sequences (https://oeis.org), OEIS Foundation Inc., CC BY-SA 4.0. Reuse must credit the OEIS and keep the share-alike licence.

Records that come from OEIS carry this licence and attribution. When you cite the data in a paper, follow OEIS's own citation guidance.

Capabilities that use OEIS

Historical archives

Historical archives

Humanities & math · Library of Congress, Europeana, OEIS

Related sources

Library of CongressEuropeana

FAQ

ScholarMuse is not an official OEIS product. It is one MCP server for academic data, and its lookup_integer_sequence tool queries OEIS. An agent connected to ScholarMuse can use OEIS without a separate server.

No. The OEIS API can be called without a key, and ScholarMuse does not ask you for one. You sign in to ScholarMuse once and your agent calls the tool.

The connector calls the search endpoint on oeis.org with fmt=json. An A-number is sent as an id: query; terms and keywords are sent as typed. No API key is sent. Responses are cached for up to 7 days, so recent edits to an OEIS entry can take a week to appear.

CC BY-SA 4.0. Attribution: The On-Line Encyclopedia of Integer Sequences (https://oeis.org), OEIS Foundation Inc., CC BY-SA 4.0. Reuse must credit the OEIS and keep the share-alike licence. Records that come from OEIS carry this licence and attribution.

Yes. Each successful call to lookup_integer_sequence uses credits, and a call that fails is not charged. Current price: Historical archives, 1 credit / call.