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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 19 |
| 7 | 49 |
| 8 | 154 |
| 9 | 415 |
| 10 | 1066 |
| 11 | 3322 |
| 12 | 10639 |
| 13 | 31279 |
| 14 | 96751 |
| 15 | 326908 |
| 16 | 1082065 |
| 17 | 3514285 |
| 18 | 12068659 |
| 19 | 42713311 |
| 20 | 148480885 |
| 21 | 523469791 |
| 22 | 1915394458 |
| 23 | 7043990266 |
| 24 | 25840482346 |
| 25 | 96913386589 |
| 26 | 370304345755 |
| 27 | 1415830556098 |
| 28 | 5458805003308 |
| 29 | 21434092603255 |
| 30 | 84865526136793 |
| 31 | 337266100883830 |
[1,1,1,1,4,10,19,49,154,415,1066,3322,10639,31279, 96751,326908,1082065,3514285,12068659,42713311, 148480885,523469791,1915394458,7043990266, 25840482346,96913386589,370304345755, 1415830556098,5458805003308,21434092603255, 84865526136793,337266100883830] |