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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 132 |
| 6 | 1058 |
| 7 | 13756 |
| 8 | 288878 |
| 9 | 9821854 |
| 10 | 540201972 |
| 11 | 48077975510 |
| 12 | 6923228473442 |
| 13 | 1613112234311988 |
| 14 | 608143312335619478 |
| 15 | 370967420524727881582 |
| 16 | 366144844057906419121436 |
| 17 | 584733315960476551336933294 |
| 18 | 1510950888441871408654635631698 |
[1,3,8,26,132,1058,13756,288878,9821854,540201972, 48077975510,6923228473442,1613112234311988, 608143312335619478,370967420524727881582, 366144844057906419121436, 584733315960476551336933294, 1510950888441871408654635631698] |