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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 27 |
| 6 | 57 |
| 7 | 123 |
| 8 | 280 |
| 9 | 666 |
| 10 | 1614 |
| 11 | 3955 |
| 12 | 9733 |
| 13 | 23949 |
| 14 | 58967 |
| 15 | 145844 |
| 16 | 363137 |
| 17 | 910339 |
| 18 | 2295192 |
| 19 | 5811070 |
| 20 | 14754567 |
| 21 | 37542078 |
| 22 | 95715596 |
| 23 | 244567665 |
| 24 | 626388406 |
| 25 | 1608131393 |
| 26 | 4137707994 |
| 27 | 10667045757 |
| 28 | 27546269363 |
| 29 | 71241831762 |
| 30 | 184508259405 |
| 31 | 478501423792 |
[1,1,2,5,12,27,57,123,280,666,1614,3955,9733, 23949,58967,145844,363137,910339,2295192,5811070, 14754567,37542078,95715596,244567665,626388406, 1608131393,4137707994,10667045757,27546269363, 71241831762,184508259405,478501423792] |