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 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 30 |
| 5 | 102 |
| 6 | 374 |
| 7 | 1430 |
| 8 | 5590 |
| 9 | 22102 |
| 10 | 87894 |
| 11 | 350550 |
| 12 | 1400150 |
| 13 | 5596502 |
| 14 | 22377814 |
| 15 | 89494870 |
| 16 | 357946710 |
| 17 | 1431721302 |
| 18 | 5726754134 |
| 19 | 22906754390 |
| 20 | 91626493270 |
| 21 | 366504924502 |
| 22 | 1466017600854 |
| 23 | 5864066209110 |
| 24 | 23456256447830 |
| 25 | 93825009014102 |
| 26 | 375300002501974 |