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| n | a(n) |
|---|---|
| 1 | 512 |
| 2 | 2616 |
| 3 | 10684 |
| 4 | 41140 |
| 5 | 150016 |
| 6 | 514920 |
| 7 | 1700100 |
| 8 | 5487356 |
| 9 | 17402796 |
| 10 | 54388900 |
| 11 | 168051612 |
| 12 | 514608380 |
| 13 | 1564152640 |
| 14 | 4724495088 |
| 15 | 14194815516 |
| 16 | 42456223192 |
| 17 | 126490940620 |
| 18 | 375582012308 |
| 19 | 1111890899408 |
| 20 | 3283117868720 |
| 21 | 9671825746548 |
[512,2616,10684,41140,150016,514920,1700100, 5487356,17402796,54388900,168051612,514608380, 1564152640,4724495088,14194815516,42456223192, 126490940620,375582012308,1111890899408, 3283117868720,9671825746548] |