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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 69 |
| 3 | 410 |
| 4 | 2261 |
| 5 | 11970 |
| 6 | 61909 |
| 7 | 315850 |
| 8 | 1598421 |
| 9 | 8050130 |
| 10 | 40425749 |
| 11 | 202656090 |
| 12 | 1014866581 |
| 13 | 5079099490 |
| 14 | 25409813589 |
| 15 | 127092049130 |
| 16 | 635589254741 |
| 17 | 3178333432050 |
| 18 | 15892828897429 |
| 19 | 79467630222970 |
| 20 | 397348609370901 |
| 21 | 1986774423719810 |
| 22 | 9933966253389269 |
[1,10,69,410,2261,11970,61909,315850,1598421, 8050130,40425749,202656090,1014866581,5079099490, 25409813589,127092049130,635589254741, 3178333432050,15892828897429,79467630222970, 397348609370901,1986774423719810,9933966253389269] |