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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 26 |
| 5 | 56 |
| 6 | 115 |
| 7 | 230 |
| 8 | 453 |
| 9 | 884 |
| 10 | 1716 |
| 11 | 3321 |
| 12 | 6416 |
| 13 | 12383 |
| 14 | 23886 |
| 15 | 46060 |
| 16 | 88803 |
| 17 | 171194 |
| 18 | 330009 |
| 19 | 636136 |
| 20 | 1226216 |
| 21 | 2363633 |
| 22 | 4556076 |
| 23 | 8782147 |
| 24 | 16928162 |
| 25 | 32630112 |
| 26 | 62896595 |
| 27 | 121237118 |
| 28 | 233692093 |
| 29 | 450456028 |
| 30 | 868281948 |
| 31 | 1673667305 |
| 32 | 3226097496 |
| 33 | 6218502903 |
[0,1,4,11,26,56,115,230,453,884,1716,3321,6416, 12383,23886,46060,88803,171194,330009,636136, 1226216,2363633,4556076,8782147,16928162,32630112, 62896595,121237118,233692093,450456028,868281948, 1673667305,3226097496,6218502903] |