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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 50 |
| 4 | 266 |
| 5 | 1466 |
| 6 | 8370 |
| 7 | 49090 |
| 8 | 294458 |
| 9 | 1798794 |
| 10 | 11156074 |
| 11 | 70069514 |
| 12 | 444822530 |
| 13 | 2849764698 |
| 14 | 18401517066 |
| 15 | 119640989514 |
| 16 | 782575127258 |
| 17 | 5146252178882 |
| 18 | 34003440381186 |
| 19 | 225635772455882 |
| 20 | 1503017848153914 |
| 21 | 10046960505610082 |
| 22 | 67372689978768714 |
| 23 | 453099298491559554 |
[1,2,10,50,266,1466,8370,49090,294458,1798794, 11156074,70069514,444822530,2849764698, 18401517066,119640989514,782575127258, 5146252178882,34003440381186,225635772455882, 1503017848153914,10046960505610082, 67372689978768714,453099298491559554] |