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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 2 |
| 6 | 7 |
| 7 | 14 |
| 8 | 34 |
| 9 | 72 |
| 10 | 157 |
| 11 | 326 |
| 12 | 689 |
| 13 | 1418 |
| 14 | 2935 |
| 15 | 6010 |
| 16 | 12304 |
| 17 | 25058 |
| 18 | 51004 |
| 19 | 103478 |
| 20 | 209767 |
| 21 | 424430 |
| 22 | 858019 |
| 23 | 1732430 |
| 24 | 3495434 |
| 25 | 7046432 |
| 26 | 14196421 |
| 27 | 28583424 |
| 28 | 57522469 |
| 29 | 115704938 |
| 30 | 232645189 |
| 31 | 467597246 |
| 32 | 939526144 |
[0,0,0,1,2,7,14,34,72,157,326,689,1418,2935,6010, 12304,25058,51004,103478,209767,424430,858019, 1732430,3495434,7046432,14196421,28583424, 57522469,115704938,232645189,467597246,939526144] |