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 | 3 |
| 3 | 6 |
| 4 | 18 |
| 5 | 49 |
| 6 | 155 |
| 7 | 486 |
| 8 | 1614 |
| 9 | 5414 |
| 10 | 18630 |
| 11 | 64828 |
| 12 | 228740 |
| 13 | 814485 |
| 14 | 2926323 |
| 15 | 10588486 |
| 16 | 38561814 |
| 17 | 141214570 |
| 18 | 519711666 |
| 19 | 1921126036 |
| 20 | 7129756188 |
| 21 | 26555090618 |
| 22 | 99228108222 |
| 23 | 371886366620 |
| 24 | 1397548389644 |
| 25 | 5265130603468 |