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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 1 |
| 7 | 4 |
| 8 | 24 |
| 9 | 218 |
| 10 | 1 |
| 11 | 5 |
| 12 | 70 |
| 13 | 22815 |
| 14 | 22409620 |
| 15 | 1 |
| 16 | 6 |
| 17 | 165 |
| 18 | 703760 |
| 19 | 9651199594275 |
| 20 | 629648865090036960064 |
| 21 | 1 |
| 22 | 7 |
| 23 | 336 |
| 24 | 10194250 |
| 25 | 96076801068337216 |
| 26 | 76983765319971869475595432431084156 |
| 27 | 272443651709491352597039736725488834366101875164020736 |
| 28 | 1 |
[1,2,1,3,6,1,4,24,218,1,5,70,22815,22409620,1,6, 165,703760,9651199594275,629648865090036960064,1, 7,336,10194250,96076801068337216, 76983765319971869475595432431084156, 27244365170949135259703973672548883436610187516402\ 0736,1] |