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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 25 |
| 6 | 43 |
| 7 | 93 |
| 8 | 220 |
| 9 | 617 |
| 10 | 1016 |
| 11 | 2039 |
| 12 | 4112 |
| 13 | 8401 |
| 14 | 17598 |
| 15 | 38292 |
| 16 | 90070 |
| 17 | 252612 |
| 18 | 415156 |
| 19 | 830319 |
| 20 | 1660672 |
| 21 | 3321521 |
| 22 | 6643838 |
| 23 | 13290772 |
| 24 | 26595030 |
| 25 | 53262532 |
| 26 | 106850150 |
| 27 | 214945816 |
| 28 | 434874798 |
| 29 | 889700788 |
| 30 | 1859656696 |
[1,2,4,9,25,43,93,220,617,1016,2039,4112,8401, 17598,38292,90070,252612,415156,830319,1660672, 3321521,6643838,13290772,26595030,53262532, 106850150,214945816,434874798,889700788, 1859656696] |