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 | 19 |
| 3 | 63 |
| 4 | 307 |
| 5 | 1095 |
| 6 | 4843 |
| 7 | 18111 |
| 8 | 76483 |
| 9 | 294327 |
| 10 | 1213147 |
| 11 | 4747119 |
| 12 | 19308979 |
| 13 | 76282599 |
| 14 | 308006731 |
| 15 | 1223430687 |
| 16 | 4919576995 |
| 17 | 19600876311 |
| 18 | 78636062395 |
| 19 | 313847102415 |
| 20 | 1257480899731 |
| 21 | 5023648225863 |
| 22 | 20113423216939 |
| 23 | 80397210315903 |
| 24 | 321758305696387 |
| 25 | 1286524863041655 |