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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 8 |
| 6 | 14 |
| 7 | 49 |
| 8 | 79 |
| 9 | 253 |
| 10 | 741 |
| 11 | 2335 |
| 12 | 6399 |
| 13 | 37905 |
| 14 | 102246 |
| 15 | 593203 |
| 16 | 2884877 |
| 17 | 16569870 |
| 18 | 80670284 |
| 19 | 832584915 |
| 20 | 3998999249 |
| 21 | 40528587997 |
| 22 | 352270529241 |
| 23 | 3516190442125 |
| 24 | 29997079375598 |
| 25 | 543310308646601 |
| 26 | 4559849026688799 |
[1,2,2,3,4,8,14,49,79,253,741,2335,6399,37905, 102246,593203,2884877,16569870,80670284,832584915, 3998999249,40528587997,352270529241,3516190442125, 29997079375598,543310308646601,4559849026688799] |