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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 19 |
| 7 | 42 |
| 8 | 88 |
| 9 | 188 |
| 10 | 393 |
| 11 | 821 |
| 12 | 1692 |
| 13 | 3483 |
| 14 | 7101 |
| 15 | 14436 |
| 16 | 29162 |
| 17 | 58703 |
| 18 | 117577 |
| 19 | 234695 |
| 20 | 466493 |
| 21 | 924149 |
| 22 | 1824100 |
| 23 | 3588957 |
| 24 | 7038072 |
| 25 | 13760324 |
| 26 | 26821365 |
| 27 | 52130255 |
| 28 | 101033183 |
| 29 | 195279030 |
| 30 | 376427128 |
| 31 | 723731809 |
| 32 | 1387917803 |
| 33 | 2655019934 |
[1,1,1,2,4,9,19,42,88,188,393,821,1692,3483,7101, 14436,29162,58703,117577,234695,466493,924149, 1824100,3588957,7038072,13760324,26821365, 52130255,101033183,195279030,376427128,723731809, 1387917803,2655019934] |