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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 20 |
| 6 | 58 |
| 7 | 139 |
| 8 | 438 |
| 9 | 1140 |
| 10 | 3418 |
| 11 | 9932 |
| 12 | 30628 |
| 13 | 88108 |
| 14 | 280662 |
| 15 | 840825 |
| 16 | 2681258 |
| 17 | 8069994 |
| 18 | 26491824 |
| 19 | 81571012 |
| 20 | 264345958 |
| 21 | 834289608 |
| 22 | 2744822564 |
| 23 | 8655497466 |
| 24 | 28654030002 |
| 25 | 91833730268 |
| 26 | 305378072266 |
| 27 | 978386996766 |
| 28 | 3289069655984 |
| 29 | 10666263089892 |
| 30 | 35684640821198 |
| 31 | 116837930295941 |
| 32 | 393934299599316 |
[1,1,2,3,10,20,58,139,438,1140,3418,9932,30628, 88108,280662,840825,2681258,8069994,26491824, 81571012,264345958,834289608,2744822564, 8655497466,28654030002,91833730268,305378072266, 978386996766,3289069655984,10666263089892, 35684640821198,116837930295941,393934299599316] |