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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 173 |
| 5 | 358 |
| 6 | 889 |
| 7 | 2136 |
| 8 | 30793 |
| 9 | 63722 |
| 10 | 158237 |
| 11 | 380196 |
| 12 | 5480981 |
| 13 | 11342158 |
| 14 | 28165297 |
| 15 | 67672752 |
| 16 | 975583825 |
| 17 | 2018840402 |
| 18 | 5013264629 |
| 19 | 12045369660 |
| 20 | 173648439869 |
| 21 | 359342249398 |
| 22 | 892332938665 |
| 23 | 2144008126728 |
| 24 | 30908446712857 |
| 25 | 63960901552442 |
| 26 | 158830249817741 |
[1,2,5,12,173,358,889,2136,30793,63722,158237, 380196,5480981,11342158,28165297,67672752, 975583825,2018840402,5013264629,12045369660, 173648439869,359342249398,892332938665, 2144008126728,30908446712857,63960901552442, 158830249817741] |