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 | 6 |
| 4 | 14 |
| 5 | 38 |
| 6 | 103 |
| 7 | 280 |
| 8 | 773 |
| 9 | 2160 |
| 10 | 6053 |
| 11 | 17064 |
| 12 | 48320 |
| 13 | 137260 |
| 14 | 391091 |
| 15 | 1117192 |
| 16 | 3198217 |
| 17 | 9173480 |
| 18 | 26357393 |
| 19 | 75845591 |
| 20 | 218550709 |
| 21 | 630536447 |
| 22 | 1821184411 |
| 23 | 5265514692 |
| 24 | 15238183779 |
| 25 | 44136519841 |
| 26 | 127940010907 |
| 27 | 371135327740 |
| 28 | 1077340058523 |
| 29 | 3129301019091 |
| 30 | 7015876423459 |