io.github.cyanheads/oeis-mcp-server
oeis-mcp-server
Identify integer sequences by terms, search the OEIS, read formulas, programs, b-files, cross-refs.
alive probed 2026-10-05 · HTTP 200
6tools
3.3ktokens in Claude Opus 5.5
3.4ktokens in Claude Code
1.7 %of a 200k context window
2.0ko200k_base estimate
280 msto initialize
75 msto list tools
- Endpoint
- https://oeis.caseyjhand.com/mcp (streamable-http)
- Host
- oeis.caseyjhand.com
- Protocol
- 2025-11-25
- Reports itself as
- oeis-mcp-server 0.1.2
- Capabilities
- logging, prompts, resources, tools
- Instructions
- 998 characters
- Claude count
- Claude Opus 5.5, measured 2026-10-05. Counted again when the tool definitions change. Method.
- Repository
- https://github.com/cyanheads/oeis-mcp-server
- Registry
- active, updated 2026-10-02 · registry entry
- Reachable
- 6 of the last 6 probes
Most expensive tools
| Tool | Tokens (o200k) | Share of this server |
|---|---|---|
| oeis_get_sequence | 508 | 25 % |
| oeis_identify_sequence | 364 | 18 % |
| oeis_get_terms | 361 | 18 % |
| oeis_get_cross_refs | 313 | 15 % |
| oeis_search_sequences | 310 | 15 % |
History
We add a row when the result changes. A server with no change keeps its last row.
| Probed | Result | Init | Tools | Claude | o200k |
|---|---|---|---|---|---|
| 2026-10-05 14:39 | alive | 280 ms | 6 | 3.3k | 2.0k |
| 2026-10-05 00:33 | alive | 194 ms | 6 | 2.0k | |
| 2026-10-04 10:04 | alive | 252 ms | 6 | 2.0k | |
| 2026-10-04 07:57 | alive | 405 ms | 6 | 2.0k | |
| 2026-10-03 20:37 | alive | 769 ms | 6 | 2.0k | |
| 2026-10-03 17:53 | alive | 398 ms | 6 | 2.0k |
Badge and feed
[](https://mcpcost.ulehla.dev/s/io.github.cyanheads/oeis-mcp-server)
An entry for every probe that changed the result, the tool count or the token cost: Atom feed. Add it to a feed reader or a Slack RSS app to hear when the server stops answering or its tool set grows.