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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 78 |
| 6 | 271 |
| 7 | 896 |
| 8 | 3228 |
| 9 | 11119 |
| 10 | 41002 |
| 11 | 145548 |
| 12 | 545187 |
| 13 | 1974923 |
| 14 | 7480699 |
| 15 | 27503349 |
| 16 | 105050951 |
| 17 | 390597492 |
| 18 | 1501505042 |
| 19 | 5632087999 |
| 20 | 21759951598 |
| 21 | 82196014521 |
| 22 | 318859845293 |
| 23 | 1211380162124 |
| 24 | 4714855246296 |
| 25 | 17997471462958 |
| 26 | 70241280052488 |
| 27 | 269196555472317 |
| 28 | 1053057343103259 |
| 29 | 4049528715390724 |
[1,1,3,8,26,78,271,896,3228,11119,41002,145548, 545187,1974923,7480699,27503349,105050951, 390597492,1501505042,5632087999,21759951598, 82196014521,318859845293,1211380162124, 4714855246296,17997471462958,70241280052488, 269196555472317,1053057343103259,4049528715390724] |