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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 2 |
| 5 | -4 |
| 6 | -1 |
| 7 | 10 |
| 8 | -3 |
| 9 | -20 |
| 10 | 19 |
| 11 | 38 |
| 12 | -70 |
| 13 | -65 |
| 14 | 221 |
| 15 | 73 |
| 16 | -640 |
| 17 | 117 |
| 18 | 1745 |
| 19 | -1223 |
| 20 | -4433 |
| 21 | 5770 |
| 22 | 10124 |
| 23 | -22007 |
| 24 | -18999 |
| 25 | 75063 |
| 26 | 19307 |
| 27 | -235725 |
| 28 | 59665 |
| 29 | 685744 |
| 30 | -525477 |
| 31 | -1832544 |
| 32 | 2531982 |
| 33 | 4364936 |
| 34 | -10007555 |
| 35 | -8468154 |
| 36 | 35302510 |
| 37 | 8542655 |
| 38 | -114305453 |
[1,1,-1,1,2,-4,-1,10,-3,-20,19,38,-70,-65,221,73, -640,117,1745,-1223,-4433,5770,10124,-22007, -18999,75063,19307,-235725,59665,685744,-525477, -1832544,2531982,4364936,-10007555,-8468154, 35302510,8542655,-114305453] |