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 | 3 |
| 2 | 6 |
| 3 | 16 |
| 4 | 40 |
| 5 | 100 |
| 6 | 251 |
| 7 | 631 |
| 8 | 1585 |
| 9 | 3981 |
| 10 | 10000 |
| 11 | 25119 |
| 12 | 63096 |
| 13 | 158489 |
| 14 | 398107 |
| 15 | 1000000 |
| 16 | 2511886 |
| 17 | 6309573 |
| 18 | 15848932 |
| 19 | 39810717 |
| 20 | 100000000 |
| 21 | 251188643 |
| 22 | 630957344 |
| 23 | 1584893192 |
| 24 | 3981071706 |
| 25 | 10000000000 |
| 26 | 25118864315 |
| 27 | 63095734448 |
| 28 | 158489319246 |
| 29 | 398107170553 |
| 30 | 1000000000000 |