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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 47 |
| 5 | 185 |
| 6 | 723 |
| 7 | 2821 |
| 8 | 11127 |
| 9 | 43825 |
| 10 | 173147 |
| 11 | 685181 |
| 12 | 2713919 |
| 13 | 10762793 |
| 14 | 42715619 |
| 15 | 169654133 |
| 16 | 674238983 |
| 17 | 2680944545 |
| 18 | 10665068907 |
| 19 | 42443750893 |
| 20 | 168973210575 |
| 21 | 672913173913 |
| 22 | 2680539263219 |
| 23 | 10680581419493 |
| 24 | 42566341729431 |
| 25 | 169678604019217 |
| 26 | 676501889994363 |
[1,3,13,47,185,723,2821,11127,43825,173147,685181, 2713919,10762793,42715619,169654133,674238983, 2680944545,10665068907,42443750893,168973210575, 672913173913,2680539263219,10680581419493, 42566341729431,169678604019217,676501889994363] |