This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 26 |
| 3 | 216 |
| 4 | 1291 |
| 5 | 5164 |
| 6 | 68313 |
| 7 | 163284 |
| 8 | 785294 |
| 9 | 3559026 |
| 10 | 26393686 |
| 11 | 129099069 |
| 12 | 254296413 |
| 13 | 816435342 |
| 14 | 4081257976 |
| 15 | 80413106314 |
| 16 | 215329205326 |
| 17 | 2463064689907 |
| 18 | 5165911014784 |
| 19 | 24832773982716 |
| 20 | 81401883640163 |
| 21 | 752766125152206 |
| 22 | 4086159158264236 |
| 23 | 21602469586893686 |
| 24 | 32659863237109026 |
| 25 | 683788466294121304 |