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 | 21 |
| 2 | 876 |
| 3 | 21489 |
| 4 | 588529 |
| 5 | 16031147 |
| 6 | 437241277 |
| 7 | 11938414614 |
| 8 | 325438086413 |
| 9 | 8875686431050 |
| 10 | 242075272701612 |
| 11 | 6602021695088725 |
| 12 | 180056949233250710 |
| 13 | 4910676438495880068 |
| 14 | 133928360921171032911 |
| 15 | 3652617573522712382545 |