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 | 5 |
| 2 | 23 |
| 3 | 153 |
| 4 | 1329 |
| 5 | 14235 |
| 6 | 181215 |
| 7 | 2672145 |
| 8 | 44781345 |
| 9 | 840523635 |
| 10 | 17465201775 |
| 11 | 397983749625 |
| 12 | 9867844134225 |
| 13 | 264469801070475 |
| 14 | 7618612476650175 |
| 15 | 234748657653134625 |
| 16 | 7703855828862818625 |
| 17 | 268263758052098683875 |
| 18 | 9879138385352252391375 |
| 19 | 383608053176023482431625 |
| 20 | 15664153113813817068080625 |