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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 34 |
| 2 | 665 |
| 3 | 8865 |
| 4 | 76249 |
| 5 | 495985 |
| 6 | 2661967 |
| 7 | 11908924 |
| 8 | 46316901 |
| 9 | 161588843 |
| 10 | 510043341 |
| 11 | 1480441810 |
| 12 | 4011008946 |
| 13 | 10193915255 |
| 14 | 24508598458 |
| 15 | 56179164262 |
| 16 | 123191992504 |
| 17 | 259647495716 |
| 18 | 528503830704 |
| 19 | 1041183396446 |
| 20 | 1991316075404 |
[1,34,665,8865,76249,495985,2661967,11908924, 46316901,161588843,510043341,1480441810, 4011008946,10193915255,24508598458,56179164262, 123191992504,259647495716,528503830704, 1041183396446,1991316075404] |