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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 16 |
| 6 | 22 |
| 7 | 70 |
| 8 | 106 |
| 9 | 1836 |
| 10 | 2639 |
| 11 | 14281 |
| 12 | 21167 |
| 13 | 167857 |
| 14 | 87932 |
| 15 | 169452 |
| 16 | 923889 |
| 17 | 3590229 |
| 18 | 950596 |
| 19 | 40366604 |
| 20 | 23213361 |
| 21 | 517630 |
| 22 | 1391957 |
| 23 | 160363133 |
| 24 | 222528683 |
| 25 | 10125035246 |
| 26 | 4324958013 |
| 27 | 81828906108 |
| 28 | 71315450571 |
| 29 | 4320297286472 |
[0,1,2,2,16,22,70,106,1836,2639,14281,21167, 167857,87932,169452,923889,3590229,950596, 40366604,23213361,517630,1391957,160363133, 222528683,10125035246,4324958013,81828906108, 71315450571,4320297286472] |