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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 30 |
| 4 | 149 |
| 5 | 576 |
| 6 | 2621 |
| 7 | 12495 |
| 8 | 59426 |
| 9 | 291819 |
| 10 | 1434777 |
| 11 | 7089514 |
| 12 | 35139759 |
| 13 | 174262279 |
| 14 | 865022922 |
| 15 | 4295106017 |
| 16 | 21330145045 |
| 17 | 105941879250 |
| 18 | 526209580143 |
| 19 | 2613748830983 |
| 20 | 12983012681014 |
| 21 | 64489686157037 |
| 22 | 320337024303633 |
[1,13,30,149,576,2621,12495,59426,291819,1434777, 7089514,35139759,174262279,865022922,4295106017, 21330145045,105941879250,526209580143, 2613748830983,12983012681014,64489686157037, 320337024303633] |