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 | 3 |
| 2 | 8 |
| 3 | 21 |
| 4 | 56 |
| 5 | 154 |
| 6 | 440 |
| 7 | 1309 |
| 8 | 4048 |
| 9 | 12958 |
| 10 | 42712 |
| 11 | 144210 |
| 12 | 496432 |
| 13 | 1735764 |
| 14 | 6145968 |
| 15 | 21986781 |
| 16 | 79331232 |
| 17 | 288307254 |
| 18 | 1054253208 |
| 19 | 3875769606 |
| 20 | 14315659632 |
| 21 | 53097586284 |
| 22 | 197677736208 |
| 23 | 738415086066 |