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 | 20 |
| 2 | 174 |
| 3 | 988 |
| 4 | 4277 |
| 5 | 15288 |
| 6 | 47320 |
| 7 | 130832 |
| 8 | 330174 |
| 9 | 772616 |
| 10 | 1696396 |
| 11 | 3527160 |
| 12 | 6995534 |
| 13 | 13312768 |
| 14 | 24426552 |
| 15 | 43385360 |
| 16 | 74847175 |
| 17 | 125777340 |
| 18 | 206390730 |
| 19 | 331405620 |
| 20 | 521690715 |
| 21 | 806403000 |
| 22 | 1225732560 |
| 23 | 1834391520 |
| 24 | 2706007980 |
| 25 | 3938612496 |
| 26 | 5661434520 |
| 27 | 8043259504 |