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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 62 |
| 6 | 264 |
| 7 | 1170 |
| 8 | 5310 |
| 9 | 24599 |
| 10 | 116092 |
| 11 | 556613 |
| 12 | 2703650 |
| 13 | 13274152 |
| 14 | 65764358 |
| 15 | 328361751 |
| 16 | 1650666672 |
| 17 | 8347486950 |
| 18 | 42437045604 |
| 19 | 216759551139 |
| 20 | 1111844674824 |
| 21 | 5724834867561 |
| 22 | 29578779083964 |
| 23 | 153307052745777 |
| 24 | 796878214632936 |
| 25 | 4153051850599218 |
[1,2,5,16,62,264,1170,5310,24599,116092,556613, 2703650,13274152,65764358,328361751,1650666672, 8347486950,42437045604,216759551139,1111844674824, 5724834867561,29578779083964,153307052745777, 796878214632936,4153051850599218] |