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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 3 |
| 3 | 10 |
| 4 | 36 |
| 5 | 99 |
| 6 | 254 |
| 7 | 598 |
| 8 | 1339 |
| 9 | 2872 |
| 10 | 5966 |
| 11 | 12071 |
| 12 | 23908 |
| 13 | 46516 |
| 14 | 89155 |
| 15 | 168702 |
| 16 | 315712 |
| 17 | 585163 |
| 18 | 1075442 |
| 19 | 1961754 |
| 20 | 3554715 |
| 21 | 6402780 |
| 22 | 11470778 |
| 23 | 20450255 |
| 24 | 36297576 |
| 25 | 64164744 |
| 26 | 113006019 |
| 27 | 198345298 |
| 28 | 347033724 |
| 29 | 605414067 |
| 30 | 1053307526 |
[0,3,10,36,99,254,598,1339,2872,5966,12071,23908, 46516,89155,168702,315712,585163,1075442,1961754, 3554715,6402780,11470778,20450255,36297576, 64164744,113006019,198345298,347033724,605414067, 1053307526] |