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 | 0 |
| 1 | -10 |
| 2 | -18 |
| 3 | -56 |
| 4 | -138 |
| 5 | -370 |
| 6 | -960 |
| 7 | -2522 |
| 8 | -6594 |
| 9 | -17272 |
| 10 | -45210 |
| 11 | -118370 |
| 12 | -309888 |
| 13 | -811306 |
| 14 | -2124018 |
| 15 | -5560760 |
| 16 | -14558250 |
| 17 | -38114002 |
| 18 | -99783744 |
| 19 | -261237242 |
| 20 | -683927970 |
| 21 | -1790546680 |
| 22 | -4687712058 |
| 23 | -12272589506 |
| 24 | -32130056448 |
| 25 | -84117579850 |
| 26 | -220222683090 |