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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 38 |
| 5 | 141 |
| 6 | 574 |
| 7 | 2345 |
| 8 | 10064 |
| 9 | 43483 |
| 10 | 191640 |
| 11 | 853025 |
| 12 | 3840296 |
| 13 | 17442407 |
| 14 | 79843694 |
| 15 | 367883558 |
| 16 | 1705065009 |
| 17 | 7941414689 |
| 18 | 37158646595 |
| 19 | 174544395929 |
| 20 | 822892445849 |
| 21 | 3891877164643 |
| 22 | 18460967216268 |
| 23 | 87800293875206 |
| 24 | 418588052068224 |
| 25 | 2000044237816727 |
| 26 | 9575710379149561 |
| 27 | 45932139441076537 |
[1,1,3,10,38,141,574,2345,10064,43483,191640, 853025,3840296,17442407,79843694,367883558, 1705065009,7941414689,37158646595,174544395929, 822892445849,3891877164643,18460967216268, 87800293875206,418588052068224,2000044237816727, 9575710379149561,45932139441076537] |