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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 5 |
| 3 | 10 |
| 4 | 20 |
| 5 | 42 |
| 6 | 93 |
| 7 | 213 |
| 8 | 504 |
| 9 | 1221 |
| 10 | 3014 |
| 11 | 7553 |
| 12 | 19158 |
| 13 | 49087 |
| 14 | 126845 |
| 15 | 330174 |
| 16 | 864884 |
| 17 | 2278138 |
| 18 | 6030218 |
| 19 | 16031950 |
| 20 | 42790362 |
| 21 | 114616360 |
| 22 | 307996874 |
| 23 | 830084080 |
| 24 | 2243193198 |
| 25 | 6076953906 |
| 26 | 16500486744 |
| 27 | 44897830740 |
| 28 | 122406923038 |
| 29 | 334333367602 |
[1,3,5,10,20,42,93,213,504,1221,3014,7553,19158, 49087,126845,330174,864884,2278138,6030218, 16031950,42790362,114616360,307996874,830084080, 2243193198,6076953906,16500486744,44897830740, 122406923038,334333367602] |