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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 9 |
| 6 | 21 |
| 7 | 37 |
| 8 | 69 |
| 9 | 113 |
| 10 | 187 |
| 11 | 286 |
| 12 | 449 |
| 13 | 657 |
| 14 | 976 |
| 15 | 1397 |
| 16 | 2003 |
| 17 | 2788 |
| 18 | 3902 |
| 19 | 5323 |
| 20 | 7284 |
| 21 | 9789 |
| 22 | 13144 |
| 23 | 17405 |
| 24 | 23052 |
| 25 | 30142 |
| 26 | 39379 |
| 27 | 50967 |
| 28 | 65842 |
| 29 | 84368 |
| 30 | 107954 |
| 31 | 137126 |
| 32 | 173893 |
[0,0,1,4,9,21,37,69,113,187,286,449,657,976,1397, 2003,2788,3902,5323,7284,9789,13144,17405,23052, 30142,39379,50967,65842,84368,107954,137126, 173893] |