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 | 3 |
| 2 | 12 |
| 3 | 39 |
| 4 | 138 |
| 5 | 548 |
| 6 | 2129 |
| 7 | 8311 |
| 8 | 32933 |
| 9 | 130750 |
| 10 | 519980 |
| 11 | 2069494 |
| 12 | 8238734 |
| 13 | 32801506 |
| 14 | 130618157 |
| 15 | 520176813 |
| 16 | 2071605150 |
| 17 | 8250287558 |
| 18 | 32857555574 |
| 19 | 130858980239 |
| 20 | 521161959522 |
| 21 | 2075594388132 |
| 22 | 8266327630092 |
| 23 | 32921750282882 |
| 24 | 131115278622574 |
| 25 | 522184203094342 |
| 26 | 2079668830404846 |