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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 17 |
| 4 | 122 |
| 5 | 257 |
| 6 | 577 |
| 7 | 1850 |
| 8 | 5626 |
| 9 | 16901 |
| 10 | 47525 |
| 11 | 140626 |
| 12 | 414737 |
| 13 | 1223237 |
| 14 | 3583450 |
| 15 | 10523537 |
| 16 | 30946970 |
| 17 | 90973445 |
| 18 | 267322501 |
| 19 | 785456677 |
| 20 | 2308418117 |
| 21 | 6784157957 |
| 22 | 19937157602 |
| 23 | 58589654810 |
| 24 | 172181842705 |
| 25 | 506006018282 |
| 26 | 1487038791365 |
| 27 | 4370064820901 |
| 28 | 12842626162922 |
[2,10,17,122,257,577,1850,5626,16901,47525,140626, 414737,1223237,3583450,10523537,30946970,90973445, 267322501,785456677,2308418117,6784157957, 19937157602,58589654810,172181842705,506006018282, 1487038791365,4370064820901,12842626162922] |