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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 4 |
| 8 | 14 |
| 9 | 41 |
| 10 | 110 |
| 11 | 278 |
| 12 | 673 |
| 13 | 1576 |
| 14 | 3599 |
| 15 | 8055 |
| 16 | 17732 |
| 17 | 38509 |
| 18 | 82683 |
| 19 | 175830 |
| 20 | 370856 |
| 21 | 776723 |
| 22 | 1616945 |
| 23 | 3348500 |
| 24 | 6902905 |
| 25 | 14174198 |
| 26 | 29004911 |
| 27 | 59175625 |
| 28 | 120414435 |
| 29 | 244468774 |
| 30 | 495340191 |
| 31 | 1001911626 |
| 32 | 2023473267 |
| 33 | 4081241473 |
| 34 | 8222198324 |
| 35 | 16548146045 |
| 36 | 33276169507 |
[0,0,0,0,0,0,1,4,14,41,110,278,673,1576,3599,8055, 17732,38509,82683,175830,370856,776723,1616945, 3348500,6902905,14174198,29004911,59175625, 120414435,244468774,495340191,1001911626, 2023473267,4081241473,8222198324,16548146045, 33276169507] |