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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 30 |
| 4 | 209 |
| 5 | 1573 |
| 6 | 12478 |
| 7 | 102714 |
| 8 | 869193 |
| 9 | 7514445 |
| 10 | 66083025 |
| 11 | 589294500 |
| 12 | 5316256278 |
| 13 | 48431659786 |
| 14 | 444928748618 |
| 15 | 4117185679310 |
| 16 | 38340948482745 |
| 17 | 359047299072777 |
| 18 | 3379057486089649 |
| 19 | 31942315551724102 |
| 20 | 303158909307122141 |
| 21 | 2887629443604011421 |
| 22 | 27595392738011189028 |
[1,1,5,30,209,1573,12478,102714,869193,7514445, 66083025,589294500,5316256278,48431659786, 444928748618,4117185679310,38340948482745, 359047299072777,3379057486089649, 31942315551724102,303158909307122141, 2887629443604011421,27595392738011189028] |