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 | 4 |
| 1 | 10 |
| 2 | 34 |
| 3 | 130 |
| 4 | 514 |
| 5 | 2050 |
| 6 | 8194 |
| 7 | 32770 |
| 8 | 131074 |
| 9 | 524290 |
| 10 | 2097154 |
| 11 | 8388610 |
| 12 | 33554434 |
| 13 | 134217730 |
| 14 | 536870914 |
| 15 | 2147483650 |
| 16 | 8589934594 |
| 17 | 34359738370 |
| 18 | 137438953474 |
| 19 | 549755813890 |
| 20 | 2199023255554 |
| 21 | 8796093022210 |
| 22 | 35184372088834 |
| 23 | 140737488355330 |
| 24 | 562949953421314 |