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 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | -1 |
| 5 | 6 |
| 6 | -5 |
| 7 | 12 |
| 8 | -11 |
| 9 | 20 |
| 10 | -19 |
| 11 | 30 |
| 12 | -29 |
| 13 | 42 |
| 14 | -41 |
| 15 | 56 |
| 16 | -55 |
| 17 | 72 |
| 18 | -71 |
| 19 | 90 |
| 20 | -89 |
| 21 | 110 |
| 22 | -109 |
| 23 | 132 |
| 24 | -131 |
| 25 | 156 |
| 26 | -155 |
| 27 | 182 |
| 28 | -181 |
| 29 | 210 |
| 30 | -209 |
| 31 | 240 |
| 32 | -239 |
| 33 | 272 |
| 34 | -271 |
| 35 | 306 |
| 36 | -305 |
| 37 | 342 |
| 38 | -341 |
| 39 | 380 |
| 40 | -379 |
| 41 | 420 |
| 42 | -419 |
| 43 | 462 |
| 44 | -461 |
| 45 | 506 |
| 46 | -505 |
| 47 | 552 |
| 48 | -551 |
| 49 | 600 |
| 50 | -599 |
| 51 | 650 |
| 52 | -649 |
| 53 | 702 |
| 54 | -701 |
| 55 | 756 |
| 56 | -755 |
| 57 | 812 |
| 58 | -811 |
| 59 | 870 |
| 60 | -869 |
| 61 | 930 |
| 62 | -929 |
| 63 | 992 |
| 64 | -991 |
| 65 | 1056 |
| 66 | -1055 |
| 67 | 1122 |
| 68 | -1121 |
| 69 | 1190 |
| 70 | -1189 |
| 71 | 1260 |
| 72 | -1259 |
| 73 | 1332 |
| 74 | -1331 |
| 75 | 1406 |