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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 45 |
| 4 | 187 |
| 5 | 821 |
| 6 | 3639 |
| 7 | 16445 |
| 8 | 75299 |
| 9 | 347041 |
| 10 | 1616443 |
| 11 | 7561899 |
| 12 | 35593793 |
| 13 | 168297467 |
| 14 | 798480657 |
| 15 | 3803381005 |
| 16 | 18162203269 |
| 17 | 86978159921 |
| 18 | 417499394667 |
| 19 | 2008036165615 |
| 20 | 9677714027555 |
| 21 | 46716157888291 |
| 22 | 225876896720627 |
| 23 | 1093684863896891 |
| 24 | 5302402827561317 |
| 25 | 25739324193084863 |
| 26 | 125081068214983069 |
[1,3,11,45,187,821,3639,16445,75299,347041, 1616443,7561899,35593793,168297467,798480657, 3803381005,18162203269,86978159921,417499394667, 2008036165615,9677714027555,46716157888291, 225876896720627,1093684863896891,5302402827561317, 25739324193084863,125081068214983069] |