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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 2 |
| 6 | 9 |
| 7 | 13 |
| 8 | 41 |
| 9 | 94 |
| 10 | 257 |
| 11 | 671 |
| 12 | 1881 |
| 13 | 5110 |
| 14 | 14301 |
| 15 | 39871 |
| 16 | 112281 |
| 17 | 316520 |
| 18 | 897297 |
| 19 | 2548819 |
| 20 | 7265383 |
| 21 | 20754748 |
| 22 | 59437181 |
| 23 | 170549237 |
| 24 | 490338539 |
| 25 | 1412147684 |
| 26 | 4073528481 |
| 27 | 11767897903 |
| 28 | 34042917197 |
| 29 | 98606864030 |
| 30 | 285960106473 |
| 31 | 830206177801 |
| 32 | 2412787265021 |
[0,1,1,3,2,9,13,41,94,257,671,1881,5110,14301, 39871,112281,316520,897297,2548819,7265383, 20754748,59437181,170549237,490338539,1412147684, 4073528481,11767897903,34042917197,98606864030, 285960106473,830206177801,2412787265021] |