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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 34 |
| 4 | 191 |
| 5 | 1071 |
| 6 | 6154 |
| 7 | 35729 |
| 8 | 209455 |
| 9 | 1236508 |
| 10 | 7341577 |
| 11 | 43792112 |
| 12 | 262230242 |
| 13 | 1575391156 |
| 14 | 9490934411 |
| 15 | 57316715079 |
| 16 | 346875036879 |
| 17 | 2103174805035 |
| 18 | 12773139313516 |
| 19 | 77689736488088 |
| 20 | 473160660856361 |
| 21 | 2885208137132852 |
| 22 | 17612514244078288 |
| 23 | 107621658416373752 |
[1,1,7,34,191,1071,6154,35729,209455,1236508, 7341577,43792112,262230242,1575391156,9490934411, 57316715079,346875036879,2103174805035, 12773139313516,77689736488088,473160660856361, 2885208137132852,17612514244078288, 107621658416373752] |