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 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 6 |
| 6 | 21 |
| 7 | 22 |
| 8 | 73 |
| 9 | 210 |
| 10 | 1693 |
| 11 | 1694 |
| 12 | 2097 |
| 13 | 2098 |
| 14 | 12997 |
| 15 | 21468 |
| 16 | 174169 |
| 17 | 174170 |
| 18 | 1986237 |
| 19 | 1986238 |
| 20 | 10178833 |
| 21 | 16875654 |
| 22 | 246551437 |
| 23 | 246551438 |
| 24 | 2032266537 |
| 25 | 3767596738 |
| 26 | 45445808989 |
| 27 | 260705796192 |
| 28 | 2932954933753 |
| 29 | 2932954933754 |
| 30 | 5496591783573 |
| 31 | 5496591783574 |