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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 5 |
| 3 | 10 |
| 4 | 20 |
| 5 | 42 |
| 6 | 91 |
| 7 | 195 |
| 8 | 415 |
| 9 | 880 |
| 10 | 1864 |
| 11 | 3952 |
| 12 | 8385 |
| 13 | 17795 |
| 14 | 37765 |
| 15 | 80138 |
| 16 | 170044 |
| 17 | 360810 |
| 18 | 765595 |
| 19 | 1624515 |
| 20 | 3447071 |
| 21 | 7314368 |
| 22 | 15520400 |
| 23 | 32932800 |
| 24 | 69880225 |
| 25 | 148279107 |
| 26 | 314634021 |
| 27 | 667623210 |
| 28 | 1416632420 |
| 29 | 3005958090 |
| 30 | 6378354619 |
[1,3,5,10,20,42,91,195,415,880,1864,3952,8385, 17795,37765,80138,170044,360810,765595,1624515, 3447071,7314368,15520400,32932800,69880225, 148279107,314634021,667623210,1416632420, 3005958090,6378354619] |