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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 10 |
| 3 | 20 |
| 4 | 35 |
| 5 | 57 |
| 6 | 89 |
| 7 | 136 |
| 8 | 205 |
| 9 | 306 |
| 10 | 454 |
| 11 | 671 |
| 12 | 989 |
| 13 | 1455 |
| 14 | 2138 |
| 15 | 3139 |
| 16 | 4606 |
| 17 | 6756 |
| 18 | 9907 |
| 19 | 14525 |
| 20 | 21293 |
| 21 | 31212 |
| 22 | 45749 |
| 23 | 67054 |
| 24 | 98278 |
| 25 | 144039 |
| 26 | 211105 |
| 27 | 309395 |
| 28 | 453446 |
| 29 | 664563 |
| 30 | 973970 |
| 31 | 1427428 |
| 32 | 2092003 |
| 33 | 3065985 |
| 34 | 4493425 |
| 35 | 6585440 |
| 36 | 9651437 |
| 37 | 14144874 |
| 38 | 20730326 |
| 39 | 30381775 |
[1,4,10,20,35,57,89,136,205,306,454,671,989,1455, 2138,3139,4606,6756,9907,14525,21293,31212,45749, 67054,98278,144039,211105,309395,453446,664563, 973970,1427428,2092003,3065985,4493425,6585440, 9651437,14144874,20730326,30381775] |