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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 88 |
| 3 | 564 |
| 4 | 2720 |
| 5 | 30946 |
| 6 | 261939 |
| 7 | 1918732 |
| 8 | 16176806 |
| 9 | 134671502 |
| 10 | 1084005062 |
| 11 | 8855022968 |
| 12 | 72556284402 |
| 13 | 592076260322 |
| 14 | 4833986775520 |
| 15 | 39491897603294 |
| 16 | 322560160507073 |
| 17 | 2634426639664265 |
| 18 | 21517102473205131 |
| 19 | 175744528043164291 |
[1,88,564,2720,30946,261939,1918732,16176806, 134671502,1084005062,8855022968,72556284402, 592076260322,4833986775520,39491897603294, 322560160507073,2634426639664265, 21517102473205131,175744528043164291] |