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 | 2 |
| 3 | 6 |
| 4 | 23 |
| 5 | 106 |
| 6 | 567 |
| 7 | 3440 |
| 8 | 23286 |
| 9 | 173704 |
| 10 | 1414102 |
| 11 | 12465119 |
| 12 | 118205428 |
| 13 | 1199306902 |
| 14 | 12958274048 |
| 15 | 148502304614 |
| 16 | 1798680392716 |
| 17 | 22953847041950 |
| 18 | 307774885768354 |
| 19 | 4325220458515307 |
| 20 | 63563589415836532 |
| 21 | 974883257009308933 |
| 22 | 15575374626562632462 |
| 23 | 258780875395778033769 |
| 24 | 4464364292401926006220 |