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 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 68 |
| 5 | 395 |
| 6 | 2450 |
| 7 | 15892 |
| 8 | 106489 |
| 9 | 731379 |
| 10 | 5121392 |
| 11 | 36425796 |
| 12 | 262425982 |
| 13 | 1911063188 |
| 14 | 14044679173 |
| 15 | 104030937139 |
| 16 | 775856119012 |
| 17 | 5821085551579 |
| 18 | 43906627941144 |
| 19 | 332742274685104 |
| 20 | 2532358764929916 |
| 21 | 19346427410500788 |
| 22 | 148312939031577504 |
| 23 | 1140578980645677208 |