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 | 11 |
| 5 | 44 |
| 6 | 185 |
| 7 | 801 |
| 8 | 3547 |
| 9 | 15961 |
| 10 | 72710 |
| 11 | 334463 |
| 12 | 1550679 |
| 13 | 7236463 |
| 14 | 33955573 |
| 15 | 160075762 |
| 16 | 757689991 |
| 17 | 3599019810 |
| 18 | 17148240314 |
| 19 | 81930357294 |
| 20 | 392402777679 |
| 21 | 1883531191109 |
| 22 | 9058879060004 |
| 23 | 43647287768424 |
| 24 | 210645440011836 |
| 25 | 1018118905986455 |
| 26 | 4927692357099550 |
| 27 | 23880341433363005 |