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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 3 |
| 3 | 10 |
| 4 | 39 |
| 5 | 100 |
| 6 | 303 |
| 7 | 782 |
| 8 | 2009 |
| 9 | 5388 |
| 10 | 12839 |
| 11 | 32658 |
| 12 | 79673 |
| 13 | 191500 |
| 14 | 459745 |
| 15 | 1090622 |
| 16 | 2569597 |
| 17 | 5932304 |
| 18 | 13906405 |
| 19 | 31740090 |
| 20 | 72160311 |
| 21 | 164296384 |
| 22 | 369673125 |
| 23 | 827781598 |
| 24 | 1834885695 |
| 25 | 4076433368 |
| 26 | 8966677703 |
| 27 | 19639987986 |
| 28 | 42751905899 |
| 29 | 92703023676 |
| 30 | 200647122467 |
[0,0,3,10,39,100,303,782,2009,5388,12839,32658, 79673,191500,459745,1090622,2569597,5932304, 13906405,31740090,72160311,164296384,369673125, 827781598,1834885695,4076433368,8966677703, 19639987986,42751905899,92703023676,200647122467] |