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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 82 |
| 5 | 297 |
| 6 | 1092 |
| 7 | 4074 |
| 8 | 15316 |
| 9 | 57993 |
| 10 | 220913 |
| 11 | 845017 |
| 12 | 3245513 |
| 13 | 12504416 |
| 14 | 48308973 |
| 15 | 187089688 |
| 16 | 726028123 |
| 17 | 2822654120 |
| 18 | 10991682069 |
| 19 | 42864045010 |
| 20 | 167373921420 |
| 21 | 654315764945 |
| 22 | 2560630856073 |
| 23 | 10030570526492 |
| 24 | 39326590305594 |
| 25 | 154311641356522 |
| 26 | 605946719764108 |
| 27 | 2381052954112297 |
[1,2,7,23,82,297,1092,4074,15316,57993,220913, 845017,3245513,12504416,48308973,187089688, 726028123,2822654120,10991682069,42864045010, 167373921420,654315764945,2560630856073, 10030570526492,39326590305594,154311641356522, 605946719764108,2381052954112297] |