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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 9 |
| 2 | 89 |
| 3 | 439 |
| 4 | 1519 |
| 5 | 4214 |
| 6 | 10038 |
| 7 | 21378 |
| 8 | 41778 |
| 9 | 76263 |
| 10 | 131703 |
| 11 | 217217 |
| 12 | 344617 |
| 13 | 528892 |
| 14 | 788732 |
| 15 | 1147092 |
| 16 | 1631796 |
| 17 | 2276181 |
| 18 | 3119781 |
| 19 | 4209051 |
| 20 | 5598131 |
| 21 | 7349650 |
| 22 | 9535570 |
| 23 | 12238070 |
| 24 | 15550470 |
| 25 | 19578195 |
| 26 | 24439779 |
| 27 | 30267909 |
| 28 | 37210509 |
| 29 | 45431864 |
| 30 | 55113784 |
[0,9,89,439,1519,4214,10038,21378,41778,76263, 131703,217217,344617,528892,788732,1147092, 1631796,2276181,3119781,4209051,5598131,7349650, 9535570,12238070,15550470,19578195,24439779, 30267909,37210509,45431864,55113784] |