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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 23 |
| 5 | 50 |
| 6 | 110 |
| 7 | 240 |
| 8 | 526 |
| 9 | 1147 |
| 10 | 2489 |
| 11 | 5368 |
| 12 | 11510 |
| 13 | 24543 |
| 14 | 52090 |
| 15 | 110109 |
| 16 | 231959 |
| 17 | 487245 |
| 18 | 1020980 |
| 19 | 2134838 |
| 20 | 4455582 |
| 21 | 9283742 |
| 22 | 19314740 |
| 23 | 40128699 |
| 24 | 83265342 |
| 25 | 172564435 |
| 26 | 357228078 |
| 27 | 738707908 |
| 28 | 1526004117 |
| 29 | 3149310585 |
| 30 | 6493394292 |
| 31 | 13376521031 |
| 32 | 27532616663 |
[0,1,4,10,23,50,110,240,526,1147,2489,5368,11510, 24543,52090,110109,231959,487245,1020980,2134838, 4455582,9283742,19314740,40128699,83265342, 172564435,357228078,738707908,1526004117, 3149310585,6493394292,13376521031,27532616663] |