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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 573 |
| 3 | 1274 |
| 4 | 4648 |
| 5 | 18191 |
| 6 | 74685 |
| 7 | 290474 |
| 8 | 1134326 |
| 9 | 4476521 |
| 10 | 17504192 |
| 11 | 68460956 |
| 12 | 268946027 |
| 13 | 1056908182 |
| 14 | 4152467108 |
| 15 | 16322047853 |
| 16 | 64182331628 |
| 17 | 252466069300 |
| 18 | 993456216706 |
| 19 | 3910523487359 |
| 20 | 15397203073949 |
| 21 | 60640330684857 |
[5,573,1274,4648,18191,74685,290474,1134326, 4476521,17504192,68460956,268946027,1056908182, 4152467108,16322047853,64182331628,252466069300, 993456216706,3910523487359,15397203073949, 60640330684857] |