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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 39 |
| 6 | 124 |
| 7 | 400 |
| 8 | 1358 |
| 9 | 4680 |
| 10 | 16821 |
| 11 | 60975 |
| 12 | 227420 |
| 13 | 854978 |
| 14 | 3284367 |
| 15 | 12695918 |
| 16 | 49903145 |
| 17 | 197196052 |
| 18 | 789692499 |
| 19 | 3176716632 |
| 20 | 12918607435 |
| 21 | 52741268340 |
| 22 | 217271153314 |
| 23 | 898126282267 |
| 24 | 3740877574014 |
| 25 | 15628602402197 |
| 26 | 65718067398013 |
| 27 | 277087115116637 |
| 28 | 1174844573892291 |
| 29 | 4993340224586904 |
[1,1,2,5,14,39,124,400,1358,4680,16821,60975, 227420,854978,3284367,12695918,49903145,197196052, 789692499,3176716632,12918607435,52741268340, 217271153314,898126282267,3740877574014, 15628602402197,65718067398013,277087115116637, 1174844573892291,4993340224586904] |