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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 19 |
| 7 | 45 |
| 8 | 106 |
| 9 | 260 |
| 10 | 643 |
| 11 | 1624 |
| 12 | 4138 |
| 13 | 10683 |
| 14 | 27790 |
| 15 | 72917 |
| 16 | 192548 |
| 17 | 511624 |
| 18 | 1366424 |
| 19 | 3666930 |
| 20 | 9881527 |
| 21 | 26730495 |
| 22 | 72556208 |
| 23 | 197562840 |
| 24 | 539479354 |
| 25 | 1477016717 |
| 26 | 4053631757 |
| 27 | 11149957667 |
| 28 | 30732671572 |
| 29 | 84871652538 |
| 30 | 234802661446 |
| 31 | 650684226827 |