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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 22 |
| 3 | 10 |
| 4 | 1089 |
| 5 | 3303 |
| 6 | 27620 |
| 7 | 163297 |
| 8 | 1242087 |
| 9 | 7872632 |
| 10 | 53760082 |
| 11 | 353252004 |
| 12 | 2390946331 |
| 13 | 15793996654 |
| 14 | 106138988508 |
| 15 | 705385250439 |
| 16 | 4723352116586 |
| 17 | 31474104782001 |
| 18 | 210349127355642 |
| 19 | 1403285636312709 |
| 20 | 9371971431288242 |
[0,22,10,1089,3303,27620,163297,1242087,7872632, 53760082,353252004,2390946331,15793996654, 106138988508,705385250439,4723352116586, 31474104782001,210349127355642,1403285636312709, 9371971431288242] |