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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 5 |
| 6 | 5 |
| 7 | 15 |
| 8 | 17 |
| 9 | 78 |
| 10 | 102 |
| 11 | 569 |
| 12 | 919 |
| 13 | 6143 |
| 14 | 11171 |
| 15 | 86081 |
| 16 | 175169 |
| 17 | 1500038 |
| 18 | 3364000 |
| 19 | 31525459 |
| 20 | 76939147 |
| 21 | 780320735 |
| 22 | 2050031495 |
| 23 | 22262632431 |
| 24 | 62282672077 |
| 25 | 716105605234 |
| 26 | 2108542401240 |
| 27 | 25363729963607 |
| 28 | 77679827847931 |
[1,1,2,2,5,5,15,17,78,102,569,919,6143,11171, 86081,175169,1500038,3364000,31525459,76939147, 780320735,2050031495,22262632431,62282672077, 716105605234,2108542401240,25363729963607, 77679827847931] |