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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 26 |
| 5 | 153 |
| 6 | 937 |
| 7 | 5991 |
| 8 | 39388 |
| 9 | 264892 |
| 10 | 1813345 |
| 11 | 12595527 |
| 12 | 88550874 |
| 13 | 628917019 |
| 14 | 4505821155 |
| 15 | 32525365501 |
| 16 | 236331968980 |
| 17 | 1727163960917 |
| 18 | 12687375261788 |
| 19 | 93626506061591 |
| 20 | 693765269582186 |
| 21 | 5159886375484379 |
| 22 | 38506369969370543 |
| 23 | 288244195882614691 |
| 24 | 2163770393221878704 |
| 25 | 16284902775963901362 |
[1,1,5,26,153,937,5991,39388,264892,1813345, 12595527,88550874,628917019,4505821155, 32525365501,236331968980,1727163960917, 12687375261788,93626506061591,693765269582186, 5159886375484379,38506369969370543, 288244195882614691,2163770393221878704, 16284902775963901362] |