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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 23 |
| 4 | 39 |
| 5 | 103 |
| 6 | 231 |
| 7 | 615 |
| 8 | 871 |
| 9 | 1895 |
| 10 | 3943 |
| 11 | 10087 |
| 12 | 18279 |
| 13 | 42855 |
| 14 | 92007 |
| 15 | 223079 |
| 16 | 288615 |
| 17 | 550759 |
| 18 | 1075047 |
| 19 | 2647911 |
| 20 | 4745063 |
| 21 | 11036519 |
| 22 | 23619431 |
| 23 | 57173863 |
| 24 | 90728295 |
| 25 | 191391591 |
| 26 | 392718183 |
| 27 | 929589095 |
| 28 | 1734895463 |
| 29 | 3882379111 |
[1,3,7,23,39,103,231,615,871,1895,3943,10087, 18279,42855,92007,223079,288615,550759,1075047, 2647911,4745063,11036519,23619431,57173863, 90728295,191391591,392718183,929589095,1734895463, 3882379111] |