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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 22 |
| 3 | 46 |
| 4 | 89 |
| 5 | 223 |
| 6 | 696 |
| 7 | 2335 |
| 8 | 8380 |
| 9 | 31001 |
| 10 | 116558 |
| 11 | 442314 |
| 12 | 1686894 |
| 13 | 6453062 |
| 14 | 24725894 |
| 15 | 94832665 |
| 16 | 363935417 |
| 17 | 1397133323 |
| 18 | 5364622673 |
| 19 | 20601302508 |
| 20 | 79119265773 |
| 21 | 303870780015 |
| 22 | 1167097983033 |
| 23 | 4482628695760 |
| 24 | 17217197273712 |
[21,22,46,89,223,696,2335,8380,31001,116558, 442314,1686894,6453062,24725894,94832665, 363935417,1397133323,5364622673,20601302508, 79119265773,303870780015,1167097983033, 4482628695760,17217197273712] |