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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 6 |
| 6 | 10 |
| 7 | 46 |
| 8 | 45 |
| 9 | 144 |
| 10 | 630 |
| 11 | 1282 |
| 12 | 3589 |
| 13 | 31208 |
| 14 | 54740 |
| 15 | 306488 |
| 16 | 2365846 |
| 17 | 8422342 |
| 18 | 41318120 |
| 19 | 642228152 |
| 20 | 1995977194 |
| 21 | 19736350274 |
| 22 | 269164334206 |
| 23 | 1690170177698 |
| 24 | 14635326322042 |
| 25 | 402751016861848 |
| 26 | 2213195936856480 |
[1,2,1,2,5,6,10,46,45,144,630,1282,3589,31208, 54740,306488,2365846,8422342,41318120,642228152, 1995977194,19736350274,269164334206,1690170177698, 14635326322042,402751016861848,2213195936856480] |