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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 23 |
| 4 | 119 |
| 5 | 489 |
| 6 | 1987 |
| 7 | 8043 |
| 8 | 32599 |
| 9 | 132713 |
| 10 | 540913 |
| 11 | 2205225 |
| 12 | 8989861 |
| 13 | 36646831 |
| 14 | 149381195 |
| 15 | 608893037 |
| 16 | 2481878351 |
| 17 | 10116219555 |
| 18 | 41234080525 |
| 19 | 168071970545 |
| 20 | 685070063741 |
| 21 | 2792383408313 |
| 22 | 11381911805631 |
| 23 | 46393311136175 |
[1,5,23,119,489,1987,8043,32599,132713,540913, 2205225,8989861,36646831,149381195,608893037, 2481878351,10116219555,41234080525,168071970545, 685070063741,2792383408313,11381911805631, 46393311136175] |