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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 44 |
| 5 | 115 |
| 6 | 312 |
| 7 | 790 |
| 8 | 2004 |
| 9 | 4908 |
| 10 | 11885 |
| 11 | 28170 |
| 12 | 65987 |
| 13 | 152079 |
| 14 | 346560 |
| 15 | 779808 |
| 16 | 1736460 |
| 17 | 3825995 |
| 18 | 8351733 |
| 19 | 18064545 |
| 20 | 38747740 |
| 21 | 82443251 |
| 22 | 174096564 |
| 23 | 364991008 |
| 24 | 759989218 |
| 25 | 1572126699 |
| 26 | 3231929735 |
| 27 | 6604498620 |
| 28 | 13419469596 |
| 29 | 27117216441 |
| 30 | 54508611399 |
| 31 | 109013531864 |
| 32 | 216956853105 |
[1,1,5,15,44,115,312,790,2004,4908,11885,28170, 65987,152079,346560,779808,1736460,3825995, 8351733,18064545,38747740,82443251,174096564, 364991008,759989218,1572126699,3231929735, 6604498620,13419469596,27117216441,54508611399, 109013531864,216956853105] |