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 | 2 |
| 2 | 13 |
| 3 | 87 |
| 4 | 619 |
| 5 | 4808 |
| 6 | 39322 |
| 7 | 332398 |
| 8 | 2880950 |
| 9 | 25424042 |
| 10 | 227529235 |
| 11 | 2059034532 |
| 12 | 18803987677 |
| 13 | 173032827655 |
| 14 | 1602470967129 |
| 15 | 14922285687184 |
| 16 | 139619172246129 |
| 17 | 1311778581969146 |
| 18 | 12369977145161275 |
| 19 | 117028833678543917 |
| 20 | 1110409801410336132 |