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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 23 |
| 5 | 83 |
| 6 | 306 |
| 7 | 1135 |
| 8 | 4257 |
| 9 | 16095 |
| 10 | 61222 |
| 11 | 233956 |
| 12 | 897499 |
| 13 | 3454211 |
| 14 | 13331358 |
| 15 | 51575877 |
| 16 | 199954871 |
| 17 | 776642435 |
| 18 | 3021505570 |
| 19 | 11772342667 |
| 20 | 45927761857 |
| 21 | 179393034333 |
| 22 | 701465614758 |
| 23 | 2745595628417 |
| 24 | 10756232646630 |
| 25 | 42174080381586 |