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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 11 |
| 2 | 74 |
| 3 | 515 |
| 4 | 3602 |
| 5 | 25211 |
| 6 | 176474 |
| 7 | 1235315 |
| 8 | 8647202 |
| 9 | 60530411 |
| 10 | 423712874 |
| 11 | 2965990115 |
| 12 | 20761930802 |
| 13 | 145333515611 |
| 14 | 1017334609274 |
| 15 | 7121342264915 |
| 16 | 49849395854402 |
| 17 | 348945770980811 |
| 18 | 2442620396865674 |
| 19 | 17098342778059715 |
[2,11,74,515,3602,25211,176474,1235315,8647202, 60530411,423712874,2965990115,20761930802, 145333515611,1017334609274,7121342264915, 49849395854402,348945770980811,2442620396865674, 17098342778059715] |