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 | 33 |
| 3 | 211 |
| 4 | 1269 |
| 5 | 7109 |
| 6 | 37881 |
| 7 | 195927 |
| 8 | 996933 |
| 9 | 5029417 |
| 10 | 25262121 |
| 11 | 126608171 |
| 12 | 633821781 |
| 13 | 3171197325 |
| 14 | 15861685497 |
| 15 | 79324281727 |
| 16 | 396666275397 |
| 17 | 1983460173617 |
| 18 | 9917674841193 |
| 19 | 49589469690579 |
| 20 | 247950578857365 |
| 21 | 1239762467069077 |