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 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 9 |
| 4 | 10 |
| 5 | 6 |
| 6 | -6 |
| 7 | -27 |
| 8 | -53 |
| 9 | -72 |
| 10 | -63 |
| 11 | 0 |
| 12 | 136 |
| 13 | 336 |
| 14 | 537 |
| 15 | 603 |
| 16 | 334 |
| 17 | -471 |
| 18 | -1878 |
| 19 | -3618 |
| 20 | -4886 |
| 21 | -4275 |
| 22 | -45 |
| 23 | 9072 |
| 24 | 22465 |
| 25 | 35904 |
| 26 | 40272 |
| 27 | 22176 |
| 28 | -31823 |
| 29 | -126093 |
| 30 | -242538 |
| 31 | -327159 |
| 32 | -285686 |
| 33 | -1674 |
| 34 | 609498 |
| 35 | 1506357 |
| 36 | 2404891 |
| 37 | 2693928 |
| 38 | 1476609 |
| 39 | -2145600 |
| 40 | -8461736 |
| 41 | -16254480 |
| 42 | -21901623 |