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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 2 |
| 2 | 2 |
| 3 | 7 |
| 4 | 29 |
| 5 | 127 |
| 6 | 727 |
| 7 | 5051 |
| 8 | 40343 |
| 9 | 362897 |
| 10 | 3628811 |
| 11 | 39916801 |
| 12 | 479001629 |
| 13 | 6227020867 |
| 14 | 87178291219 |
| 15 | 1307674368043 |
| 16 | 20922789888023 |
| 17 | 355687428096031 |
| 18 | 6402373705728037 |
| 19 | 121645100408832089 |
| 20 | 2432902008176640029 |
| 21 | 51090942171709440031 |
| 22 | 1124000727777607680031 |
[2,2,2,7,29,127,727,5051,40343,362897,3628811, 39916801,479001629,6227020867,87178291219, 1307674368043,20922789888023,355687428096031, 6402373705728037,121645100408832089, 2432902008176640029,51090942171709440031, 1124000727777607680031] |