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 | 9 |
| 3 | 26 |
| 4 | 69 |
| 5 | 183 |
| 6 | 485 |
| 7 | 1283 |
| 8 | 3395 |
| 9 | 8983 |
| 10 | 23768 |
| 11 | 62886 |
| 12 | 166380 |
| 13 | 440202 |
| 14 | 1164665 |
| 15 | 3081415 |
| 16 | 8152659 |
| 17 | 21569910 |
| 18 | 57068618 |
| 19 | 150989371 |
| 20 | 399480328 |
| 21 | 1056925602 |
| 22 | 2796362297 |
| 23 | 7398479214 |
| 24 | 19574536080 |
| 25 | 51789354498 |
| 26 | 137021752562 |
| 27 | 362525481486 |
| 28 | 959152267937 |
| 29 | 2537678370405 |
| 30 | 6714065875561 |
| 31 | 17763748592841 |