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 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 28 |
| 5 | 65 |
| 6 | 151 |
| 7 | 351 |
| 8 | 816 |
| 9 | 1897 |
| 10 | 4410 |
| 11 | 10252 |
| 12 | 23833 |
| 13 | 55405 |
| 14 | 128801 |
| 15 | 299426 |
| 16 | 696081 |
| 17 | 1618192 |
| 18 | 3761840 |
| 19 | 8745217 |
| 20 | 20330163 |
| 21 | 47261895 |
| 22 | 109870576 |
| 23 | 255418101 |
| 24 | 593775046 |
| 25 | 1380359512 |
| 26 | 3208946545 |
| 27 | 7459895657 |
| 28 | 17342153393 |
| 29 | 40315615410 |
| 30 | 93722435101 |