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 | 128 |
| 1 | 279936 |
| 2 | 10000000 |
| 3 | 105413504 |
| 4 | 612220032 |
| 5 | 2494357888 |
| 6 | 8031810176 |
| 7 | 21870000000 |
| 8 | 52523350144 |
| 9 | 114415582592 |
| 10 | 230539333248 |
| 11 | 435817657216 |
| 12 | 781250000000 |
| 13 | 1338925209984 |
| 14 | 2207984167552 |
| 15 | 3521614606208 |
| 16 | 5455160701056 |
| 17 | 8235430000000 |
| 18 | 12151280273024 |
| 19 | 17565568854912 |
| 20 | 24928547056768 |