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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 157 |
| 4 | 1409 |
| 5 | 8237 |
| 6 | 35165 |
| 7 | 120809 |
| 8 | 351865 |
| 9 | 903921 |
| 10 | 2102065 |
| 11 | 4511365 |
| 12 | 9056021 |
| 13 | 17194093 |
| 14 | 31125005 |
| 15 | 54080341 |
| 16 | 90666045 |
| 17 | 147314445 |
[1,13,157,1409,8237,35165,120809,351865,903921, 2102065,4511365,9056021,17194093,31125005, 54080341,90666045,147314445] |