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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 4 |
| 5 | 12 |
| 6 | 17 |
| 7 | 50 |
| 8 | 73 |
| 9 | 212 |
| 10 | 315 |
| 11 | 909 |
| 12 | 1365 |
| 13 | 3931 |
| 14 | 5940 |
| 15 | 17122 |
| 16 | 25960 |
| 17 | 75053 |
| 18 | 113951 |
| 19 | 330917 |
| 20 | 502399 |
| 21 | 1467067 |
| 22 | 2224888 |
| 23 | 6537922 |
| 24 | 9896852 |
| 25 | 29281109 |
| 26 | 44218651 |
| 27 | 131765882 |
| 28 | 198432519 |
| 29 | 595663485 |
| 30 | 894311205 |
| 31 | 2704572795 |
[1,1,3,4,12,17,50,73,212,315,909,1365,3931,5940, 17122,25960,75053,113951,330917,502399,1467067, 2224888,6537922,9896852,29281109,44218651, 131765882,198432519,595663485,894311205, 2704572795] |