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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 7 |
| 4 | 20 |
| 5 | 45 |
| 6 | 92 |
| 7 | 170 |
| 8 | 296 |
| 9 | 486 |
| 10 | 766 |
| 11 | 1161 |
| 12 | 1708 |
| 13 | 2443 |
| 14 | 3416 |
| 15 | 4676 |
| 16 | 6288 |
| 17 | 8316 |
| 18 | 10842 |
| 19 | 13947 |
| 20 | 17732 |
| 21 | 22297 |
| 22 | 27764 |
| 23 | 34254 |
| 24 | 41912 |
| 25 | 50882 |
| 26 | 61334 |
| 27 | 73437 |
| 28 | 87388 |
| 29 | 103383 |
| 30 | 121648 |
| 31 | 142408 |
| 32 | 165920 |
| 33 | 192440 |
| 34 | 222258 |
| 35 | 255663 |
| 36 | 292980 |
| 37 | 334533 |
| 38 | 380684 |
| 39 | 431794 |
| 40 | 488264 |
[0,2,7,20,45,92,170,296,486,766,1161,1708,2443, 3416,4676,6288,8316,10842,13947,17732,22297,27764, 34254,41912,50882,61334,73437,87388,103383,121648, 142408,165920,192440,222258,255663,292980,334533, 380684,431794,488264] |