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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 42 |
| 3 | 230 |
| 4 | 1211 |
| 5 | 6237 |
| 6 | 31732 |
| 7 | 160300 |
| 8 | 806421 |
| 9 | 4046867 |
| 10 | 20278622 |
| 11 | 101525970 |
| 12 | 508028431 |
| 13 | 2541337897 |
| 14 | 12710276712 |
| 15 | 63562145240 |
| 16 | 317843011241 |
| 17 | 1589311911327 |
| 18 | 7946850122002 |
| 19 | 39735122306110 |
| 20 | 198678226618851 |
| 21 | 993398978359157 |
| 22 | 4967018427590492 |
| 23 | 24835162745336580 |
[1,7,42,230,1211,6237,31732,160300,806421,4046867, 20278622,101525970,508028431,2541337897, 12710276712,63562145240,317843011241, 1589311911327,7946850122002,39735122306110, 198678226618851,993398978359157,4967018427590492, 24835162745336580] |