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| n | a(n) |
|---|---|
| 1 | 216 |
| 2 | 260 |
| 3 | 1146 |
| 4 | 2848 |
| 5 | 9945 |
| 6 | 28434 |
| 7 | 87119 |
| 8 | 254174 |
| 9 | 732978 |
| 10 | 2062353 |
| 11 | 5663089 |
| 12 | 15156140 |
| 13 | 39373663 |
| 14 | 99199976 |
| 15 | 241889509 |
| 16 | 570721800 |
| 17 | 1303028175 |
| 18 | 2880190406 |
| 19 | 6168364480 |
| 20 | 12813006924 |
| 21 | 25845550887 |
| 22 | 50691467373 |
| 23 | 96800121980 |
| 24 | 180213143357 |
[216,260,1146,2848,9945,28434,87119,254174,732978, 2062353,5663089,15156140,39373663,99199976, 241889509,570721800,1303028175,2880190406, 6168364480,12813006924,25845550887,50691467373, 96800121980,180213143357] |