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 | 4 |
| 2 | 11 |
| 3 | 29 |
| 4 | 76 |
| 5 | 199 |
| 6 | 521 |
| 7 | 1364 |
| 8 | 3571 |
| 9 | 9349 |
| 10 | 24476 |
| 11 | 64079 |
| 12 | 167761 |
| 13 | 439204 |
| 14 | 1149851 |
| 15 | 3010349 |
| 16 | 7881196 |
| 17 | 20633239 |
| 18 | 54018521 |
| 19 | 141422324 |
| 20 | 370248451 |
| 21 | 969323029 |
| 22 | 2537720636 |
| 23 | 6643838879 |
| 24 | 17393796001 |
| 25 | 45537549124 |
| 26 | 119218851371 |
| 27 | 312119004989 |
| 28 | 817138163596 |
| 29 | 2139295485799 |