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 | 1 |
| 3 | 6 |
| 4 | 19 |
| 5 | 79 |
| 6 | 306 |
| 7 | 1247 |
| 8 | 5069 |
| 9 | 20889 |
| 10 | 86479 |
| 11 | 360205 |
| 12 | 1506462 |
| 13 | 6324176 |
| 14 | 26630423 |
| 15 | 112439094 |
| 16 | 475838291 |
| 17 | 2017827545 |
| 18 | 8572102713 |
| 19 | 36474080228 |
| 20 | 155418445421 |
| 21 | 663102388605 |
| 22 | 2832471934357 |
| 23 | 12111891668431 |
| 24 | 51841780973922 |
| 25 | 222092855692496 |
| 26 | 952237575555176 |
| 27 | 4085873505697131 |
| 28 | 17544024146446621 |