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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 25 |
| 9 | 66 |
| 10 | 165 |
| 11 | 394 |
| 12 | 914 |
| 13 | 2068 |
| 14 | 4607 |
| 15 | 10093 |
| 16 | 21818 |
| 17 | 46592 |
| 18 | 98498 |
| 19 | 206452 |
| 20 | 429670 |
| 21 | 888818 |
| 22 | 1829005 |
| 23 | 3746802 |
| 24 | 7645511 |
| 25 | 15549306 |
| 26 | 31534322 |
| 27 | 63800562 |
| 28 | 128823111 |
| 29 | 259678348 |
| 30 | 522715526 |
| 31 | 1050957282 |
| 32 | 2110953835 |
| 33 | 4236623798 |
| 34 | 8497083721 |
| 35 | 17032615177 |
[0,0,0,0,0,1,3,9,25,66,165,394,914,2068,4607, 10093,21818,46592,98498,206452,429670,888818, 1829005,3746802,7645511,15549306,31534322, 63800562,128823111,259678348,522715526,1050957282, 2110953835,4236623798,8497083721,17032615177] |