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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 29 |
| 5 | 88 |
| 6 | 268 |
| 7 | 812 |
| 8 | 2449 |
| 9 | 7366 |
| 10 | 22124 |
| 11 | 66406 |
| 12 | 199261 |
| 13 | 597836 |
| 14 | 1793572 |
| 15 | 5380792 |
| 16 | 16142465 |
| 17 | 48427498 |
| 18 | 145282612 |
| 19 | 435847970 |
| 20 | 1307544061 |
| 21 | 3922632352 |
| 22 | 11767897244 |
| 23 | 35303691940 |
| 24 | 105911076049 |
| 25 | 317733228398 |
| 26 | 953199685468 |
| 27 | 2859599056702 |
| 28 | 8578797170429 |
| 29 | 25736391511636 |
[1,2,4,10,29,88,268,812,2449,7366,22124,66406, 199261,597836,1793572,5380792,16142465,48427498, 145282612,435847970,1307544061,3922632352, 11767897244,35303691940,105911076049,317733228398, 953199685468,2859599056702,8578797170429, 25736391511636] |