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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 16 |
| 6 | 77 |
| 7 | 582 |
| 8 | 8002 |
| 9 | 205538 |
| 10 | 10010657 |
| 11 | 912838330 |
| 12 | 154634281045 |
| 13 | 48597689465264 |
| 14 | 28412286324844316 |
| 15 | 31024936551325074359 |
| 16 | 63533058735488301141874 |
| 17 | 244916078109873267213212830 |
| 18 | 1783406527132994841804241539063 |
| 19 | 24605674622456537969150523621546114 |
[1,1,2,5,16,77,582,8002,205538,10010657,912838330, 154634281045,48597689465264,28412286324844316, 31024936551325074359,63533058735488301141874, 244916078109873267213212830, 1783406527132994841804241539063, 24605674622456537969150523621546114] |