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 | 5 |
| 2 | 30 |
| 3 | 186 |
| 4 | 1276 |
| 5 | 9828 |
| 6 | 86279 |
| 7 | 866474 |
| 8 | 9924846 |
| 9 | 128592118 |
| 10 | 1864888539 |
| 11 | 29950693288 |
| 12 | 527584198445 |
| 13 | 10109318656565 |
| 14 | 209256249845854 |
| 15 | 4651751087878667 |
| 16 | 110501782280985273 |
| 17 | 2792991694461152344 |
| 18 | 74832356485576239136 |
| 19 | 2118333127408342718683 |
| 20 | 63169771935593153194107 |