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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 22 |
| 7 | 52 |
| 8 | 72 |
| 9 | 146 |
| 10 | 313 |
| 11 | 738 |
| 12 | 1156 |
| 13 | 2829 |
| 14 | 6772 |
| 15 | 9520 |
| 16 | 18496 |
| 17 | 53643 |
| 18 | 75154 |
| 19 | 162438 |
| 20 | 312328 |
| 21 | 600116 |
| 22 | 1513186 |
| 23 | 4023888 |
| 24 | 4737152 |
| 25 | 9741609 |
| 26 | 23182093 |
| 27 | 38478994 |
| 28 | 76286020 |
| 29 | 166236537 |
| 30 | 311977264 |
| 31 | 921787428 |
| 32 | 1212203072 |
| 33 | 2962424994 |
[0,1,2,4,9,22,52,72,146,313,738,1156,2829,6772, 9520,18496,53643,75154,162438,312328,600116, 1513186,4023888,4737152,9741609,23182093,38478994, 76286020,166236537,311977264,921787428,1212203072, 2962424994] |