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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 62 |
| 5 | 301 |
| 6 | 1450 |
| 7 | 6882 |
| 8 | 32156 |
| 9 | 148093 |
| 10 | 673394 |
| 11 | 3028246 |
| 12 | 13487908 |
| 13 | 59577298 |
| 14 | 261255012 |
| 15 | 1138378276 |
| 16 | 4932592056 |
| 17 | 21267076637 |
| 18 | 91289277250 |
| 19 | 390312067278 |
| 20 | 1662864320084 |
| 21 | 7061599302214 |
| 22 | 29900598469548 |
| 23 | 126269921669660 |
| 24 | 531939145476232 |
| 25 | 2235903406963506 |
[1,1,3,13,62,301,1450,6882,32156,148093,673394, 3028246,13487908,59577298,261255012,1138378276, 4932592056,21267076637,91289277250,390312067278, 1662864320084,7061599302214,29900598469548, 126269921669660,531939145476232,2235903406963506] |