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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 19 |
| 5 | 48 |
| 6 | 135 |
| 7 | 373 |
| 8 | 1085 |
| 9 | 3184 |
| 10 | 9590 |
| 11 | 29258 |
| 12 | 90833 |
| 13 | 285352 |
| 14 | 908006 |
| 15 | 2919953 |
| 16 | 9487330 |
| 17 | 31111997 |
| 18 | 102934602 |
| 19 | 343389708 |
| 20 | 1154684849 |
| 21 | 3912345408 |
| 22 | 13353796977 |
| 23 | 45906197103 |
| 24 | 158915480378 |
| 25 | 553897148543 |
| 26 | 1943627750652 |
| 27 | 6865605601382 |
| 28 | 24411508473314 |
| 29 | 87364180212671 |
| 30 | 314682145679491 |
[1,1,3,7,19,48,135,373,1085,3184,9590,29258,90833, 285352,908006,2919953,9487330,31111997,102934602, 343389708,1154684849,3912345408,13353796977, 45906197103,158915480378,553897148543, 1943627750652,6865605601382,24411508473314, 87364180212671,314682145679491] |