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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 128 |
| 5 | 551 |
| 6 | 2450 |
| 7 | 11032 |
| 8 | 50478 |
| 9 | 232937 |
| 10 | 1085177 |
| 11 | 5086575 |
| 12 | 23984271 |
| 13 | 113611413 |
| 14 | 540413923 |
| 15 | 2579476276 |
| 16 | 12350731189 |
| 17 | 59294369466 |
| 18 | 285353149406 |
| 19 | 1376172818179 |
| 20 | 6649649064765 |
| 21 | 32186279252284 |
| 22 | 156035943399738 |
| 23 | 757519998218711 |
| 24 | 3682389598680916 |
| 25 | 17921784874501360 |
| 26 | 87319248714390897 |
[1,2,8,30,128,551,2450,11032,50478,232937,1085177, 5086575,23984271,113611413,540413923,2579476276, 12350731189,59294369466,285353149406, 1376172818179,6649649064765,32186279252284, 156035943399738,757519998218711,3682389598680916, 17921784874501360,87319248714390897] |