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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 5 |
| 7 | 9 |
| 8 | 28 |
| 9 | 43 |
| 10 | 97 |
| 11 | 281 |
| 12 | 507 |
| 13 | 1286 |
| 14 | 3666 |
| 15 | 7494 |
| 16 | 20470 |
| 17 | 58725 |
| 18 | 132484 |
| 19 | 381700 |
| 20 | 1113180 |
| 21 | 2719887 |
| 22 | 8171219 |
| 23 | 24337511 |
| 24 | 63524916 |
| 25 | 197606643 |
| 26 | 602261524 |
| 27 | 1662206380 |
| 28 | 5328738685 |
| 29 | 16628469912 |
| 30 | 48148703533 |
| 31 | 158544768073 |
| 32 | 506473892417 |
| 33 | 1529218062752 |
| 34 | 5159071807165 |
[1,0,1,1,1,4,5,9,28,43,97,281,507,1286,3666,7494, 20470,58725,132484,381700,1113180,2719887,8171219, 24337511,63524916,197606643,602261524,1662206380, 5328738685,16628469912,48148703533,158544768073, 506473892417,1529218062752,5159071807165] |