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 | 19 |
| 5 | 59 |
| 6 | 176 |
| 7 | 502 |
| 8 | 1374 |
| 9 | 3630 |
| 10 | 9312 |
| 11 | 23320 |
| 12 | 57279 |
| 13 | 138536 |
| 14 | 331032 |
| 15 | 783630 |
| 16 | 1841867 |
| 17 | 4306172 |
| 18 | 10028276 |
| 19 | 23288394 |
| 20 | 53974959 |
| 21 | 124925967 |
| 22 | 288878550 |
| 23 | 667602492 |
| 24 | 1542254655 |
| 25 | 3562000916 |
| 26 | 8225719574 |
| 27 | 18994263354 |
| 28 | 43858728367 |
| 29 | 101270779744 |
| 30 | 233836327750 |
| 31 | 539935689810 |