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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 85 |
| 5 | 332 |
| 6 | 1369 |
| 7 | 5870 |
| 8 | 25945 |
| 9 | 117374 |
| 10 | 540805 |
| 11 | 2528675 |
| 12 | 11966923 |
| 13 | 57206972 |
| 14 | 275824159 |
| 15 | 1339721519 |
| 16 | 6549093013 |
| 17 | 32195473406 |
| 18 | 159065828029 |
| 19 | 789395034701 |
| 20 | 3933239089903 |
| 21 | 19668745466636 |
| 22 | 98679891233803 |
| 23 | 496570499905832 |
| 24 | 2505670304785615 |
| 25 | 12675395921692394 |
| 26 | 64270076976110203 |
| 27 | 326580624341708693 |
| 28 | 1662796531746045157 |
| 29 | 8481930651824392268 |
| 30 | 43341418581113085697 |
[1,2,7,23,85,332,1369,5870,25945,117374,540805, 2528675,11966923,57206972,275824159,1339721519, 6549093013,32195473406,159065828029,789395034701, 3933239089903,19668745466636,98679891233803, 496570499905832,2505670304785615, 12675395921692394,64270076976110203, 326580624341708693,1662796531746045157, 8481930651824392268,43341418581113085697] |