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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 28 |
| 4 | 66 |
| 5 | 136 |
| 6 | 253 |
| 7 | 435 |
| 8 | 703 |
| 9 | 1081 |
| 10 | 1596 |
| 11 | 2278 |
| 12 | 3160 |
| 13 | 4278 |
| 14 | 5671 |
| 15 | 7381 |
| 16 | 9453 |
| 17 | 11935 |
| 18 | 14878 |
| 19 | 18336 |
| 20 | 22366 |
| 21 | 27028 |
| 22 | 32385 |
| 23 | 38503 |
| 24 | 45451 |
| 25 | 53301 |
| 26 | 62128 |
| 27 | 72010 |
| 28 | 83028 |
| 29 | 95266 |
| 30 | 108811 |
| 31 | 123753 |
| 32 | 140185 |
| 33 | 158203 |
| 34 | 177906 |
| 35 | 199396 |
| 36 | 222778 |
| 37 | 248160 |
| 38 | 275653 |
| 39 | 305371 |
[1,3,10,28,66,136,253,435,703,1081,1596,2278,3160, 4278,5671,7381,9453,11935,14878,18336,22366,27028, 32385,38503,45451,53301,62128,72010,83028,95266, 108811,123753,140185,158203,177906,199396,222778, 248160,275653,305371] |