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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 7 |
| 6 | 13 |
| 7 | 30 |
| 8 | 64 |
| 9 | 150 |
| 10 | 338 |
| 11 | 794 |
| 12 | 1836 |
| 13 | 4313 |
| 14 | 10067 |
| 15 | 23621 |
| 16 | 55313 |
| 17 | 129647 |
| 18 | 303720 |
| 19 | 711078 |
| 20 | 1665037 |
| 21 | 3894282 |
| 22 | 9111343 |
| 23 | 21290577 |
| 24 | 49770844 |
| 25 | 116206114 |
| 26 | 271435025 |
| 27 | 633298969 |
| 28 | 1478178004 |
| 29 | 3446626028 |
| 30 | 8039424324 |
| 31 | 18734704111 |
| 32 | 43673728357 |
| 33 | 101723730306 |
[1,1,1,2,3,7,13,30,64,150,338,794,1836,4313,10067, 23621,55313,129647,303720,711078,1665037,3894282, 9111343,21290577,49770844,116206114,271435025, 633298969,1478178004,3446626028,8039424324, 18734704111,43673728357,101723730306] |