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 | 3 |
| 3 | 3 |
| 4 | -5 |
| 5 | -30 |
| 6 | -84 |
| 7 | -182 |
| 8 | -342 |
| 9 | -585 |
| 10 | -935 |
| 11 | -1419 |
| 12 | -2067 |
| 13 | -2912 |
| 14 | -3990 |
| 15 | -5340 |
| 16 | -7004 |
| 17 | -9027 |
| 18 | -11457 |
| 19 | -14345 |
| 20 | -17745 |
| 21 | -21714 |
| 22 | -26312 |
| 23 | -31602 |
| 24 | -37650 |
| 25 | -44525 |
| 26 | -52299 |
| 27 | -61047 |
| 28 | -70847 |
| 29 | -81780 |
| 30 | -93930 |
| 31 | -107384 |
| 32 | -122232 |
| 33 | -138567 |
| 34 | -156485 |
| 35 | -176085 |
| 36 | -197469 |
| 37 | -220742 |
| 38 | -246012 |
| 39 | -273390 |
| 40 | -302990 |