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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 14 |
| 5 | 89 |
| 6 | 716 |
| 7 | 6967 |
| 8 | 79524 |
| 9 | 1041541 |
| 10 | 15393100 |
| 11 | 253377811 |
| 12 | 4596600004 |
| 13 | 91112351537 |
| 14 | 1959073928124 |
| 15 | 45414287553455 |
| 16 | 1129046241331316 |
| 17 | 29965290866974493 |
| 18 | 845605519848379436 |
| 19 | 25282324544244718411 |
| 20 | 798348403914242674980 |
| 21 | 26549922456617388029641 |