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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 41 |
| 3 | 225 |
| 4 | 1195 |
| 5 | 6227 |
| 6 | 32059 |
| 7 | 163727 |
| 8 | 831505 |
| 9 | 4206145 |
| 10 | 21215481 |
| 11 | 106782837 |
| 12 | 536618341 |
| 13 | 2693492305 |
| 14 | 13507578125 |
| 15 | 67693008145 |
| 16 | 339066121115 |
| 17 | 1697664211795 |
| 18 | 8497396194275 |
| 19 | 42522326235175 |
| 20 | 212749477704695 |
| 21 | 1064285646397915 |
| 22 | 5323532330953295 |
| 23 | 26625895085494075 |
[1,7,41,225,1195,6227,32059,163727,831505,4206145, 21215481,106782837,536618341,2693492305, 13507578125,67693008145,339066121115, 1697664211795,8497396194275,42522326235175, 212749477704695,1064285646397915,5323532330953295, 26625895085494075] |