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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 12 |
| 6 | 36 |
| 7 | 89 |
| 8 | 322 |
| 9 | 1137 |
| 10 | 4704 |
| 11 | 19839 |
| 12 | 88508 |
| 13 | 399680 |
| 14 | 1839947 |
| 15 | 8533488 |
| 16 | 39893901 |
| 17 | 187393550 |
| 18 | 884153396 |
| 19 | 4185740195 |
| 20 | 19876594537 |
| 21 | 94633345608 |
| 22 | 451615319433 |
| 23 | 2159769331317 |
| 24 | 10348546548695 |
| 25 | 49672000435724 |
| 26 | 238804871206358 |
| 27 | 1149792978954373 |
| 28 | 5543621482141513 |
[1,1,2,3,7,12,36,89,322,1137,4704,19839,88508, 399680,1839947,8533488,39893901,187393550, 884153396,4185740195,19876594537,94633345608, 451615319433,2159769331317,10348546548695, 49672000435724,238804871206358,1149792978954373, 5543621482141513] |