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 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 13 |
| 5 | 25 |
| 6 | 137 |
| 7 | 245 |
| 8 | 871 |
| 9 | 517 |
| 10 | 4629 |
| 11 | 8349 |
| 12 | 45517 |
| 13 | 83317 |
| 14 | 1074679 |
| 15 | 1992127 |
| 16 | 7424789 |
| 17 | 13901189 |
| 18 | 78403447 |
| 19 | 147940327 |
| 20 | 280060651 |
| 21 | 531718651 |
| 22 | 11133725681 |
| 23 | 21243819521 |
| 24 | 40621501691 |
| 25 | 15565330735 |
| 26 | 388375065019 |
| 27 | 248882304985 |
| 28 | 479199924517 |
| 29 | 923951191477 |
| 30 | 2973006070891 |