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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 13 |
| 4 | 26 |
| 5 | 72 |
| 6 | 175 |
| 7 | 407 |
| 8 | 1005 |
| 9 | 2450 |
| 10 | 5893 |
| 11 | 14318 |
| 12 | 34780 |
| 13 | 84221 |
| 14 | 204245 |
| 15 | 495483 |
| 16 | 1201256 |
| 17 | 2912843 |
| 18 | 7064014 |
| 19 | 17129250 |
| 20 | 41536473 |
| 21 | 100724269 |
| 22 | 244248135 |
| 23 | 592280544 |
| 24 | 1436238121 |
| 25 | 3482767494 |
| 26 | 8445435610 |
| 27 | 20479537209 |
| 28 | 49661306333 |
| 29 | 120424822297 |
[1,6,13,26,72,175,407,1005,2450,5893,14318,34780, 84221,204245,495483,1201256,2912843,7064014, 17129250,41536473,100724269,244248135,592280544, 1436238121,3482767494,8445435610,20479537209, 49661306333,120424822297] |