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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 20 |
| 7 | 35 |
| 8 | 56 |
| 9 | 85 |
| 10 | 131 |
| 11 | 231 |
| 12 | 506 |
| 13 | 1287 |
| 14 | 3367 |
| 15 | 8464 |
| 16 | 20026 |
| 17 | 44609 |
| 18 | 94334 |
| 19 | 191710 |
| 20 | 380190 |
| 21 | 748924 |
| 22 | 1491735 |
| 23 | 3044927 |
| 24 | 6398259 |
| 25 | 13770795 |
| 26 | 30031820 |
| 27 | 65615746 |
| 28 | 142422743 |
| 29 | 305750022 |
| 30 | 648652029 |
| 31 | 1362500345 |
| 32 | 2843775112 |
| 33 | 5922703731 |
| 34 | 12356169575 |
[0,0,1,4,10,20,35,56,85,131,231,506,1287,3367, 8464,20026,44609,94334,191710,380190,748924, 1491735,3044927,6398259,13770795,30031820, 65615746,142422743,305750022,648652029,1362500345, 2843775112,5922703731,12356169575] |