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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 22 |
| 6 | 29 |
| 7 | 51 |
| 8 | 173 |
| 9 | 210 |
| 10 | 262 |
| 11 | 417 |
| 12 | 746 |
| 13 | 12341 |
| 14 | 207220 |
| 15 | 498538 |
| 16 | 1286415 |
| 17 | 2351289 |
| 18 | 3702952 |
| 19 | 7664494 |
| 20 | 54693034 |
| 21 | 75971438 |
| 22 | 269954954 |
| 23 | 6674693008 |
| 24 | 13449203581 |
| 25 | 59799655308 |
| 26 | 98912303039 |
| 27 | 948887634688 |
| 28 | 3557757020909 |
| 29 | 5898230078743 |
[1,2,4,7,22,29,51,173,210,262,417,746,12341, 207220,498538,1286415,2351289,3702952,7664494, 54693034,75971438,269954954,6674693008, 13449203581,59799655308,98912303039,948887634688, 3557757020909,5898230078743] |