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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 32 |
| 5 | 155 |
| 6 | 1043 |
| 7 | 7083 |
| 8 | 51983 |
| 9 | 393064 |
| 10 | 3069809 |
| 11 | 24522342 |
| 12 | 199837021 |
| 13 | 1655355627 |
| 14 | 13907476161 |
| 15 | 118275808160 |
| 16 | 1016657106858 |
| 17 | 8821284816805 |
| 18 | 77181267608093 |
| 19 | 680346219098844 |
| 20 | 6037537131435871 |
| 21 | 53904120217352519 |
| 22 | 483921982054548241 |
| 23 | 4366269495618350828 |
| 24 | 39577142154691122910 |
[1,2,6,32,155,1043,7083,51983,393064,3069809, 24522342,199837021,1655355627,13907476161, 118275808160,1016657106858,8821284816805, 77181267608093,680346219098844,6037537131435871, 53904120217352519,483921982054548241, 4366269495618350828,39577142154691122910] |