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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 14 |
| 6 | 35 |
| 7 | 86 |
| 8 | 235 |
| 9 | 660 |
| 10 | 1968 |
| 11 | 6078 |
| 12 | 19570 |
| 13 | 65129 |
| 14 | 224057 |
| 15 | 793794 |
| 16 | 2892656 |
| 17 | 10819274 |
| 18 | 41480851 |
| 19 | 162783153 |
| 20 | 653115031 |
| 21 | 2676107761 |
| 22 | 11187573667 |
| 23 | 47675621875 |
| 24 | 206936072980 |
| 25 | 914179405191 |
| 26 | 4107584622566 |
| 27 | 18759751255220 |
| 28 | 87036191538839 |
| 29 | 409986093418733 |
[1,1,2,3,7,14,35,86,235,660,1968,6078,19570,65129, 224057,793794,2892656,10819274,41480851,162783153, 653115031,2676107761,11187573667,47675621875, 206936072980,914179405191,4107584622566, 18759751255220,87036191538839,409986093418733] |