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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 13 |
| 3 | 130 |
| 4 | 1518 |
| 5 | 19358 |
| 6 | 261323 |
| 7 | 3670828 |
| 8 | 53100530 |
| 9 | 785657529 |
| 10 | 11834135909 |
| 11 | 180863294507 |
| 12 | 2797643204500 |
| 13 | 43715591710804 |
| 14 | 689030031494554 |
| 15 | 10941710269299893 |
| 16 | 174889301792724294 |
| 17 | 2811464199460768704 |
| 18 | 45426696813655278251 |
[1,2,13,130,1518,19358,261323,3670828,53100530, 785657529,11834135909,180863294507,2797643204500, 43715591710804,689030031494554,10941710269299893, 174889301792724294,2811464199460768704, 45426696813655278251] |