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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 38 |
| 7 | 117 |
| 8 | 375 |
| 9 | 1224 |
| 10 | 4095 |
| 11 | 13925 |
| 12 | 48006 |
| 13 | 167259 |
| 14 | 588189 |
| 15 | 2084948 |
| 16 | 7442125 |
| 17 | 26725125 |
| 18 | 96485782 |
| 19 | 350002509 |
| 20 | 1275061385 |
| 21 | 4662936808 |
| 22 | 17111964241 |
| 23 | 62996437297 |
| 24 | 232589316700 |
| 25 | 861028450579 |
| 26 | 3195272504259 |
| 27 | 11884475937910 |
| 28 | 44295733523881 |
| 29 | 165420418500155 |