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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 7 |
| 5 | 18 |
| 6 | 49 |
| 7 | 120 |
| 8 | 264 |
| 9 | 544 |
| 10 | 1100 |
| 11 | 2256 |
| 12 | 4736 |
| 13 | 10080 |
| 14 | 21456 |
| 15 | 45312 |
| 16 | 94850 |
| 17 | 197412 |
| 18 | 410134 |
| 19 | 852968 |
| 20 | 1778382 |
| 21 | 3719364 |
| 22 | 7806338 |
| 23 | 16451280 |
| 24 | 34835184 |
| 25 | 74164800 |
| 26 | 158854536 |
| 27 | 342478432 |
| 28 | 743432288 |
| 29 | 1625079936 |
| 30 | 3576582592 |
| 31 | 7922065408 |
| 32 | 17648409603 |
[1,2,3,4,7,18,49,120,264,544,1100,2256,4736,10080, 21456,45312,94850,197412,410134,852968,1778382, 3719364,7806338,16451280,34835184,74164800, 158854536,342478432,743432288,1625079936, 3576582592,7922065408,17648409603] |