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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 12 |
| 6 | 23 |
| 7 | 42 |
| 8 | 75 |
| 9 | 135 |
| 10 | 248 |
| 11 | 460 |
| 12 | 849 |
| 13 | 1554 |
| 14 | 2837 |
| 15 | 5192 |
| 16 | 9527 |
| 17 | 17490 |
| 18 | 32083 |
| 19 | 58809 |
| 20 | 107781 |
| 21 | 197578 |
| 22 | 362280 |
| 23 | 664320 |
| 24 | 1218069 |
| 25 | 2233202 |
| 26 | 4094289 |
| 27 | 7506602 |
| 28 | 13763219 |
| 29 | 25234674 |
| 30 | 46266927 |
| 31 | 84828138 |
| 32 | 155528132 |
| 33 | 285154061 |
| 34 | 522819002 |
| 35 | 958568628 |
| 36 | 1757496665 |
| 37 | 3222295912 |
[1,2,2,3,6,12,23,42,75,135,248,460,849,1554,2837, 5192,9527,17490,32083,58809,107781,197578,362280, 664320,1218069,2233202,4094289,7506602,13763219, 25234674,46266927,84828138,155528132,285154061, 522819002,958568628,1757496665,3222295912] |