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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 62 |
| 6 | 201 |
| 7 | 605 |
| 8 | 2101 |
| 9 | 6624 |
| 10 | 23279 |
| 11 | 76574 |
| 12 | 271210 |
| 13 | 918146 |
| 14 | 3282137 |
| 15 | 11238893 |
| 16 | 40673789 |
| 17 | 141042188 |
| 18 | 513109423 |
| 19 | 1799944820 |
| 20 | 6574646252 |
| 21 | 23298560696 |
| 22 | 85395592241 |
| 23 | 304350318826 |
| 24 | 1120679472528 |
| 25 | 4017613299798 |
| 26 | 14831846057264 |
| 27 | 53456773456522 |
| 28 | 197791164281572 |
| 29 | 716440662966534 |
| 30 | 2655844304710287 |
[1,1,3,7,21,62,201,605,2101,6624,23279,76574, 271210,918146,3282137,11238893,40673789,141042188, 513109423,1799944820,6574646252,23298560696, 85395592241,304350318826,1120679472528, 4017613299798,14831846057264,53456773456522, 197791164281572,716440662966534,2655844304710287] |