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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 2 |
| 8 | 9 |
| 9 | 18 |
| 10 | 57 |
| 11 | 114 |
| 12 | 312 |
| 13 | 624 |
| 14 | 1578 |
| 15 | 3156 |
| 16 | 7599 |
| 17 | 15198 |
| 18 | 35401 |
| 19 | 70802 |
| 20 | 161052 |
| 21 | 322104 |
| 22 | 719790 |
| 23 | 1439580 |
| 24 | 3173090 |
| 25 | 6346180 |
| 26 | 13836426 |
| 27 | 27672852 |
| 28 | 59803104 |
| 29 | 119606208 |
| 30 | 256596276 |
| 31 | 513192552 |
| 32 | 1094249019 |
| 33 | 2188498038 |
| 34 | 4642178601 |
| 35 | 9284357202 |
[0,0,0,0,0,0,1,2,9,18,57,114,312,624,1578,3156, 7599,15198,35401,70802,161052,322104,719790, 1439580,3173090,6346180,13836426,27672852, 59803104,119606208,256596276,513192552,1094249019, 2188498038,4642178601,9284357202] |