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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 21 |
| 6 | 49 |
| 7 | 115 |
| 8 | 269 |
| 9 | 630 |
| 10 | 1474 |
| 11 | 3450 |
| 12 | 8073 |
| 13 | 18893 |
| 14 | 44212 |
| 15 | 103465 |
| 16 | 242125 |
| 17 | 566617 |
| 18 | 1325982 |
| 19 | 3103035 |
| 20 | 7261648 |
| 21 | 16993545 |
| 22 | 39767898 |
| 23 | 93063924 |
| 24 | 217786044 |
| 25 | 509657890 |
| 26 | 1192689641 |
| 27 | 2791104828 |
| 28 | 6531679192 |
| 29 | 15285285161 |
| 30 | 35770272112 |
| 31 | 83708766611 |
| 32 | 195893326791 |
[1,1,2,4,9,21,49,115,269,630,1474,3450,8073,18893, 44212,103465,242125,566617,1325982,3103035, 7261648,16993545,39767898,93063924,217786044, 509657890,1192689641,2791104828,6531679192, 15285285161,35770272112,83708766611,195893326791] |