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 | 5 |
| 2 | 23 |
| 3 | 47 |
| 4 | 251 |
| 5 | 1889 |
| 6 | 7793 |
| 7 | 43451 |
| 8 | 243161 |
| 9 | 726893 |
| 10 | 759821 |
| 11 | 1820111 |
| 12 | 1820111 |
| 13 | 10141499 |
| 14 | 19725473 |
| 15 | 19725473 |
| 16 | 136209239 |
| 17 | 400414121 |
| 18 | 400414121 |
| 19 | 489144599 |
| 20 | 489144599 |
| 21 | 766319189 |
| 22 | 766319189 |
| 23 | 21549657539 |
| 24 | 21549657539 |
| 25 | 21549657539 |
| 26 | 140432294381 |
| 27 | 140432294381 |
| 28 | 437339303279 |
| 29 | 1871100711071 |
| 30 | 3258583681877 |