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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 15 |
| 3 | 94 |
| 4 | 661 |
| 5 | 4983 |
| 6 | 39363 |
| 7 | 321587 |
| 8 | 2694860 |
| 9 | 23035341 |
| 10 | 200068651 |
| 11 | 1760558682 |
| 12 | 15663027711 |
| 13 | 140648129383 |
| 14 | 1273083938979 |
| 15 | 11603500739475 |
| 16 | 106404140837773 |
| 17 | 980977232554344 |
| 18 | 9087285865886766 |
| 19 | 84541177049414342 |
| 20 | 789545725457924023 |
| 21 | 7399515198155161271 |
| 22 | 69568021610270590583 |
| 23 | 655960254857760518109 |
| 24 | 6201585037793334756198 |
| 25 | 58775103307105512895151 |
[1,3,15,94,661,4983,39363,321587,2694860,23035341, 200068651,1760558682,15663027711,140648129383, 1273083938979,11603500739475,106404140837773, 980977232554344,9087285865886766, 84541177049414342,789545725457924023, 7399515198155161271,69568021610270590583, 655960254857760518109,6201585037793334756198, 58775103307105512895151] |