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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 13 |
| 5 | 41 |
| 6 | 137 |
| 7 | 445 |
| 8 | 1525 |
| 9 | 5249 |
| 10 | 18321 |
| 11 | 64821 |
| 12 | 231069 |
| 13 | 831129 |
| 14 | 3010137 |
| 15 | 10968429 |
| 16 | 40189957 |
| 17 | 147969137 |
| 18 | 547163873 |
| 19 | 2031245413 |
| 20 | 7567313965 |
| 21 | 28282674185 |
| 22 | 106016940841 |
| 23 | 398474757149 |
| 24 | 1501425771797 |
| 25 | 5670242384737 |
| 26 | 21459558843697 |
| 27 | 81375882450581 |
| 28 | 309148795708605 |
| 29 | 1176476820260985 |
[1,1,1,5,13,41,137,445,1525,5249,18321,64821, 231069,831129,3010137,10968429,40189957,147969137, 547163873,2031245413,7567313965,28282674185, 106016940841,398474757149,1501425771797, 5670242384737,21459558843697,81375882450581, 309148795708605,1176476820260985] |