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 | 11 |
| 2 | 20 |
| 3 | 38 |
| 4 | 72 |
| 5 | 138 |
| 6 | 264 |
| 7 | 508 |
| 8 | 976 |
| 9 | 1882 |
| 10 | 3624 |
| 11 | 6996 |
| 12 | 13488 |
| 13 | 26054 |
| 14 | 50264 |
| 15 | 97124 |
| 16 | 187440 |
| 17 | 362250 |
| 18 | 699240 |
| 19 | 1351492 |
| 20 | 2609008 |
| 21 | 5042950 |
| 22 | 9735768 |
| 23 | 18818772 |
| 24 | 36332016 |
| 25 | 70229066 |
| 26 | 135588200 |
| 27 | 262091348 |
| 28 | 506012592 |
| 29 | 978124038 |
| 30 | 1888445784 |
| 31 | 3650380228 |