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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 184 |
| 3 | 2701 |
| 4 | 40456 |
| 5 | 306860 |
| 6 | 9391936 |
| 7 | 144644749 |
| 8 | 2238445480 |
| 9 | 17386135604 |
| 10 | 541801226176 |
| 11 | 2115779182678 |
| 12 | 132472258939840 |
| 13 | 1038616414507808 |
| 14 | 32621327116946944 |
| 15 | 512963507737401997 |
| 16 | 8075477240446327528 |
| 17 | 63629398756188443588 |
| 18 | 2007225253307641799872 |
| 19 | 7921211894405933627674 |
| 20 | 500517296244244008379456 |
[1,13,184,2701,40456,306860,9391936,144644749, 2238445480,17386135604,541801226176,2115779182678, 132472258939840,1038616414507808, 32621327116946944,512963507737401997, 8075477240446327528,63629398756188443588, 2007225253307641799872,7921211894405933627674, 500517296244244008379456] |