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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 128 |
| 5 | 549 |
| 6 | 2450 |
| 7 | 11046 |
| 8 | 50673 |
| 9 | 234383 |
| 10 | 1094288 |
| 11 | 5140068 |
| 12 | 24286027 |
| 13 | 115257393 |
| 14 | 549211095 |
| 15 | 2625763721 |
| 16 | 12591106792 |
| 17 | 60531714120 |
| 18 | 291672527621 |
| 19 | 1408264922792 |
| 20 | 6811785194023 |
| 21 | 33002323933080 |
| 22 | 160128596210190 |
| 23 | 777991490254078 |
| 24 | 3784531914550388 |
| 25 | 18430465713070713 |
| 26 | 89847986852919897 |
[1,2,8,30,128,549,2450,11046,50673,234383,1094288, 5140068,24286027,115257393,549211095,2625763721, 12591106792,60531714120,291672527621, 1408264922792,6811785194023,33002323933080, 160128596210190,777991490254078,3784531914550388, 18430465713070713,89847986852919897] |