https://github.com/23prime/oeis2

Interface for Online Encyclopedia of Integer Sequences (OEIS).
https://github.com/23prime/oeis2

haskell oeis

Last synced: 4 months ago
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Interface for Online Encyclopedia of Integer Sequences (OEIS).

• Host: GitHub
• URL: https://github.com/23prime/oeis2
• Owner: 23prime
• License: bsd-3-clause
• Created: 2018-09-23T18:50:05.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2024-11-07T07:10:33.000Z (over 1 year ago)
• Last Synced: 2025-10-21T13:53:47.100Z (4 months ago)
• Topics: haskell, oeis
• Language: Haskell
• Homepage:
• Size: 127 KB
• Stars: 6
• Watchers: 1
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
# oeis2

[![GitHub Actions](https://github.com/23prime/oeis2/actions/workflows/test.yml/badge.svg)](https://github.com/23prime/oeis2/actions/workflows/test.yml)

[![Haskell](https://img.shields.io/badge/Language-Haskell-yellowgreen.svg)](https://www.haskell.org)

[![Hackage version](https://img.shields.io/hackage/v/oeis2.svg?label=Hackage&color=4cc41c)](https://hackage.haskell.org/package/oeis2)

[![Stackage version](https://www.stackage.org/package/oeis2/badge/lts?label=Stackage)](https://www.stackage.org/package/oeis2)

[![BSD3](https://img.shields.io/badge/License-BSD-blue.svg)](https://en.wikipedia.org/wiki/BSD_License)

Haskell interface for [Online Encyclopedia of Integer Sequences](https://oeis.org/); homage to [oeis](http://hackage.haskell.org/package/oeis2).

## Difference from  [oeis](http://hackage.haskell.org/package/oeis)

- Source data of OEIS.  

  : [oeis](http://hackage.haskell.org/package/oeis) use `fmt=text`, but this library use `fmt=json`.

- Possible to get all search results.

- Search functions from ID or sub-sequence are merged.

- Possibele to search from **other** than ID or sub-sequence.

- Support for HTTPS.

## Usage

Add import statement.

```haskell

import Math.OEIS

```

- Get all search results from sub-sequence

  - If `n == 0`, you get all search results.

    ```haskell

    ghci>searchSeq (SubSeq [1,2,3,4]) 0

    [OEIS {number = "A000027", ids = ["M0472","N0173"], seqData = [1,2,3,4,5,6,7,...

    ghci>length it

    53

    ```

  - Otherwise, you get first `n` search results.

    ```haskell

    ghci>searchSeq (SubSeq [1,2,3,4]) 17

    [OEIS {number = "A000027", ids = ["M0472","N0173"], seqData = [1,2,3,4,5,6,7,8,9,

    ghci>length it

    17

    ```

- Get first few terms from sub-sequence

  ```haskell

  ghci>getSeqData (SubSeq [1,2,2,3,3,3,4,4,4,4])

  Just [1,2,2,3,3,3,4,4,4,4,5,5,5,5,5,6,6,6,6,6,6,7,7,7,7,7,7,7,...

  ```

- Get Mathematica function from sub-sequence

  ```haskell

  ghci>mathematica <$> lookupSeq (SubSeq [1,2,2,3,3,3,4,4,4,4])

  Just ["a[1] = 1; a[n_] := a[n] = a[n - a[n - 1]] + 1 (* _Branko Curgus_, May 12 2009 *)","Table[n, {n, 13}, {n}] // Flatten (* _Robert G. Wilson v_, May 11 2010 *)"]

  ```

- If no search result

  ```haskell

  ghci>lookupSeq (ID "1145141919893")

  Nothing

  ```