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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 51 |
| 5 | 114 |
| 6 | 136 |
| 7 | 149 |
| 8 | 1388 |
| 9 | 3654 |
| 10 | 3961 |
| 11 | 41614 |
| 12 | 2975365 |
| 13 | 4120126 |
| 14 | 5760908 |
| 15 | 11210809 |
| 16 | 21235067 |
| 17 | 43239302 |
| 18 | 156258546 |
| 19 | 230627452 |
| 20 | 595763433 |
| 21 | 4709180601 |
| 22 | 148918280487 |
| 23 | 841708059551 |
| 24 | 2895551449652 |
| 25 | 5660433533409 |
| 26 | 6575950336213 |
[1,1,2,6,51,114,136,149,1388,3654,3961,41614, 2975365,4120126,5760908,11210809,21235067, 43239302,156258546,230627452,595763433,4709180601, 148918280487,841708059551,2895551449652, 5660433533409,6575950336213] |