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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 11 |
| 7 | 25 |
| 8 | 64 |
| 9 | 168 |
| 10 | 434 |
| 11 | 1136 |
| 12 | 3046 |
| 13 | 8246 |
| 14 | 22400 |
| 15 | 61290 |
| 16 | 169036 |
| 17 | 468628 |
| 18 | 1304390 |
| 19 | 3646104 |
| 20 | 10232796 |
| 21 | 28814306 |
| 22 | 81376616 |
| 23 | 230462906 |
| 24 | 654363034 |
| 25 | 1862260359 |
| 26 | 5311064061 |
| 27 | 15176758091 |
| 28 | 43448083792 |
| 29 | 124593820615 |
| 30 | 357853635931 |
| 31 | 1029326055479 |
| 32 | 2964817204082 |
[1,1,1,2,5,11,25,64,168,434,1136,3046,8246,22400, 61290,169036,468628,1304390,3646104,10232796, 28814306,81376616,230462906,654363034,1862260359, 5311064061,15176758091,43448083792,124593820615, 357853635931,1029326055479,2964817204082] |