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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 5 |
| 6 | 7 |
| 7 | 18 |
| 8 | 29 |
| 9 | 75 |
| 10 | 132 |
| 11 | 332 |
| 12 | 651 |
| 13 | 1580 |
| 14 | 3268 |
| 15 | 7961 |
| 16 | 16966 |
| 17 | 40709 |
| 18 | 89851 |
| 19 | 215461 |
| 20 | 484064 |
| 21 | 1159568 |
| 22 | 2641812 |
| 23 | 6337448 |
| 24 | 14622880 |
| 25 | 35051341 |
| 26 | 81609747 |
| 27 | 196326305 |
| 28 | 459909847 |
| 29 | 1107083238 |
| 30 | 2611592457 |
| 31 | 6299122736 |
| 32 | 14926657167 |
| 33 | 36069213786 |
| 34 | 85809507332 |
[1,1,2,2,5,7,18,29,75,132,332,651,1580,3268,7961, 16966,40709,89851,215461,484064,1159568,2641812, 6337448,14622880,35051341,81609747,196326305, 459909847,1107083238,2611592457,6299122736, 14926657167,36069213786,85809507332] |