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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 19 |
| 7 | 45 |
| 8 | 106 |
| 9 | 259 |
| 10 | 634 |
| 11 | 1571 |
| 12 | 3886 |
| 13 | 9636 |
| 14 | 23819 |
| 15 | 58805 |
| 16 | 144762 |
| 17 | 355643 |
| 18 | 871563 |
| 19 | 2131756 |
| 20 | 5203504 |
| 21 | 12679584 |
| 22 | 30844884 |
| 23 | 74921740 |
| 24 | 181721534 |
| 25 | 440177403 |
| 26 | 1064871279 |
| 27 | 2573043334 |
| 28 | 6210105218 |
| 29 | 14971861206 |
| 30 | 36057450646 |
[1,1,1,2,4,9,19,45,106,259,634,1571,3886,9636, 23819,58805,144762,355643,871563,2131756,5203504, 12679584,30844884,74921740,181721534,440177403, 1064871279,2573043334,6210105218,14971861206, 36057450646] |