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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 86 |
| 6 | 338 |
| 7 | 1318 |
| 8 | 5106 |
| 9 | 19718 |
| 10 | 76066 |
| 11 | 293398 |
| 12 | 1131794 |
| 13 | 4366374 |
| 14 | 16846018 |
| 15 | 64995254 |
| 16 | 250765298 |
| 17 | 967503814 |
| 18 | 3732821922 |
| 19 | 14401956182 |
| 20 | 55565542354 |
| 21 | 214382633062 |
| 22 | 827129764994 |
| 23 | 3191227078902 |
| 24 | 12312373271986 |
| 25 | 47503525349126 |
| 26 | 183277819294562 |
[1,2,6,22,86,338,1318,5106,19718,76066,293398, 1131794,4366374,16846018,64995254,250765298, 967503814,3732821922,14401956182,55565542354, 214382633062,827129764994,3191227078902, 12312373271986,47503525349126,183277819294562] |