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 | 3 |
| 3 | 6 |
| 4 | 21 |
| 5 | 50 |
| 6 | 108 |
| 7 | 364 |
| 8 | 987 |
| 9 | 1938 |
| 10 | 6150 |
| 11 | 17622 |
| 12 | 34776 |
| 13 | 121160 |
| 14 | 306852 |
| 15 | 549000 |
| 16 | 2178309 |
| 17 | 5701290 |
| 18 | 11197764 |
| 19 | 39083988 |
| 20 | 93031050 |
| 21 | 191708244 |
| 22 | 697884066 |
| 23 | 1836283246 |
| 24 | 3605645232 |
| 25 | 11442062750 |
| 26 | 32888033880 |
| 27 | 64700678454 |