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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 38 |
| 4 | 136 |
| 5 | 486 |
| 6 | 1760 |
| 7 | 6466 |
| 8 | 24042 |
| 9 | 90238 |
| 10 | 341190 |
| 11 | 1297574 |
| 12 | 4958114 |
| 13 | 19019254 |
| 14 | 73196994 |
| 15 | 282492254 |
| 16 | 1092867904 |
| 17 | 4236849774 |
| 18 | 16455966944 |
| 19 | 64020347914 |
| 20 | 249431257704 |
| 21 | 973100041934 |
| 22 | 3800867789884 |
| 23 | 14862066265434 |
| 24 | 58170868424084 |
[2,10,38,136,486,1760,6466,24042,90238,341190, 1297574,4958114,19019254,73196994,282492254, 1092867904,4236849774,16455966944,64020347914, 249431257704,973100041934,3800867789884, 14862066265434,58170868424084] |