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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 34 |
| 5 | 87 |
| 6 | 212 |
| 7 | 471 |
| 8 | 858 |
| 9 | 740 |
| 10 | -3674 |
| 11 | -29291 |
| 12 | -141951 |
| 13 | -576379 |
| 14 | -2111677 |
| 15 | -7161898 |
| 16 | -22646026 |
| 17 | -66408560 |
| 18 | -176815194 |
| 19 | -403468266 |
| 20 | -641064024 |
| 21 | 337909918 |
| 22 | 9269952852 |
| 23 | 55908644837 |
| 24 | 256989808831 |
| 25 | 1033152002312 |
| 26 | 3792152422259 |
| 27 | 12903091079930 |
| 28 | 40749582818221 |
[1,2,5,13,34,87,212,471,858,740,-3674,-29291, -141951,-576379,-2111677,-7161898,-22646026, -66408560,-176815194,-403468266,-641064024, 337909918,9269952852,55908644837,256989808831, 1033152002312,3792152422259,12903091079930, 40749582818221] |