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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 37 |
| 5 | 106 |
| 6 | 331 |
| 7 | 981 |
| 8 | 3473 |
| 9 | 9010 |
| 10 | 49481 |
| 11 | -7435 |
| 12 | 1744909 |
| 13 | -13392950 |
| 14 | 186659383 |
| 15 | -2369054219 |
| 16 | 33839782689 |
| 17 | -510323573086 |
| 18 | 8221794054733 |
| 19 | -140449867800547 |
| 20 | 2538204766893461 |
| 21 | -48376680944601302 |
| 22 | 969915363800997571 |
| 23 | -20407191628360339979 |
[1,2,5,13,37,106,331,981,3473,9010,49481,-7435, 1744909,-13392950,186659383,-2369054219, 33839782689,-510323573086,8221794054733, -140449867800547,2538204766893461, -48376680944601302,969915363800997571, -20407191628360339979] |