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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 13 |
| 5 | 32 |
| 6 | 92 |
| 7 | 218 |
| 8 | 576 |
| 9 | 1698 |
| 10 | 4300 |
| 11 | 11770 |
| 12 | 34914 |
| 13 | 91105 |
| 14 | 254438 |
| 15 | 759488 |
| 16 | 2030618 |
| 17 | 5746274 |
| 18 | 17189858 |
| 19 | 46698068 |
| 20 | 133334440 |
| 21 | 399479982 |
| 22 | 1099206284 |
| 23 | 3159208516 |
| 24 | 9470895658 |
| 25 | 26313455375 |
| 26 | 76003857800 |
| 27 | 227935595004 |
| 28 | 638304618462 |
| 29 | 1850933165704 |
| 30 | 5551816202580 |