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 | 4 |
| 2 | 27 |
| 3 | 119 |
| 4 | 497 |
| 5 | 2023 |
| 6 | 8149 |
| 7 | 32692 |
| 8 | 130938 |
| 9 | 524050 |
| 10 | 2096730 |
| 11 | 8387859 |
| 12 | 33553102 |
| 13 | 134215364 |
| 14 | 536866711 |
| 15 | 2147476180 |
| 16 | 8589921317 |
| 17 | 34359714770 |
| 18 | 137438911520 |
| 19 | 549755739309 |
| 20 | 2199023122967 |
| 21 | 8796092786503 |
| 22 | 35184371669802 |
| 23 | 140737487610388 |
| 24 | 562949952096975 |