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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 15 |
| 6 | 39 |
| 7 | 97 |
| 8 | 302 |
| 9 | 817 |
| 10 | 2435 |
| 11 | 7105 |
| 12 | 21500 |
| 13 | 63697 |
| 14 | 206038 |
| 15 | 663263 |
| 16 | 2159140 |
| 17 | 6975073 |
| 18 | 23040857 |
| 19 | 75117391 |
| 20 | 251186106 |
| 21 | 855285955 |
| 22 | 2942402740 |
| 23 | 10063076773 |
| 24 | 34691521836 |
| 25 | 119449516957 |
| 26 | 413353318719 |
| 27 | 1448193096705 |
| 28 | 5134958790412 |
| 29 | 18208618646053 |
| 30 | 64646350213523 |
| 31 | 229783838224857 |
| 32 | 817714839981072 |
[1,1,2,3,8,15,39,97,302,817,2435,7105,21500,63697, 206038,663263,2159140,6975073,23040857,75117391, 251186106,855285955,2942402740,10063076773, 34691521836,119449516957,413353318719, 1448193096705,5134958790412,18208618646053, 64646350213523,229783838224857,817714839981072] |