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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 30 |
| 6 | 78 |
| 7 | 206 |
| 8 | 552 |
| 9 | 1498 |
| 10 | 4105 |
| 11 | 11340 |
| 12 | 31541 |
| 13 | 88237 |
| 14 | 248076 |
| 15 | 700478 |
| 16 | 1985397 |
| 17 | 5646129 |
| 18 | 16104378 |
| 19 | 46056513 |
| 20 | 132031176 |
| 21 | 379315946 |
| 22 | 1091890772 |
| 23 | 3148736064 |
| 24 | 9095091878 |
| 25 | 26310816944 |
| 26 | 76219704957 |
| 27 | 221085782559 |
| 28 | 642058752476 |
| 29 | 1866693825362 |
| 30 | 5432795508417 |
[1,1,2,5,12,30,78,206,552,1498,4105,11340,31541, 88237,248076,700478,1985397,5646129,16104378, 46056513,132031176,379315946,1091890772, 3148736064,9095091878,26310816944,76219704957, 221085782559,642058752476,1866693825362, 5432795508417] |