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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 12 |
| 8 | 25 |
| 9 | 52 |
| 10 | 113 |
| 11 | 251 |
| 12 | 560 |
| 13 | 1268 |
| 14 | 2896 |
| 15 | 6680 |
| 16 | 15527 |
| 17 | 36301 |
| 18 | 85364 |
| 19 | 201747 |
| 20 | 479040 |
| 21 | 1141953 |
| 22 | 2732737 |
| 23 | 6560655 |
| 24 | 15799567 |
| 25 | 38154309 |
| 26 | 92378578 |
| 27 | 224192754 |
| 28 | 545292987 |
| 29 | 1328985026 |
| 30 | 3245140686 |
| 31 | 7938052589 |
[1,1,1,2,3,6,12,25,52,113,251,560,1268,2896,6680, 15527,36301,85364,201747,479040,1141953,2732737, 6560655,15799567,38154309,92378578,224192754, 545292987,1328985026,3245140686,7938052589] |