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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 22 |
| 6 | 83 |
| 7 | 326 |
| 8 | 1300 |
| 9 | 5195 |
| 10 | 20776 |
| 11 | 83098 |
| 12 | 332387 |
| 13 | 1329543 |
| 14 | 5318166 |
| 15 | 21272659 |
| 16 | 85090631 |
| 17 | 340362521 |
| 18 | 1361450080 |
| 19 | 5445800316 |
| 20 | 21783201259 |
| 21 | 87132805033 |
| 22 | 348531220128 |
| 23 | 1394124880509 |
| 24 | 5576499522030 |
| 25 | 22305998088117 |
[1,2,3,7,22,83,326,1300,5195,20776,83098,332387, 1329543,5318166,21272659,85090631,340362521, 1361450080,5445800316,21783201259,87132805033, 348531220128,1394124880509,5576499522030, 22305998088117] |