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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 18 |
| 5 | 41 |
| 6 | 223 |
| 7 | 933 |
| 8 | 4888 |
| 9 | 10709 |
| 10 | 37015 |
| 11 | 47724 |
| 12 | 84739 |
| 13 | 217202 |
| 14 | 12248051 |
| 15 | 24713304 |
| 16 | 36961355 |
| 17 | 61674659 |
| 18 | 221985332 |
| 19 | 505645323 |
| 20 | 2750211947 |
| 21 | 11506493111 |
| 22 | 60282677502 |
| 23 | 132071848115 |
| 24 | 456498221847 |
| 25 | 588570069962 |
| 26 | 1045068291809 |
| 27 | 2678706653580 |
[1,2,3,5,18,41,223,933,4888,10709,37015,47724, 84739,217202,12248051,24713304,36961355,61674659, 221985332,505645323,2750211947,11506493111, 60282677502,132071848115,456498221847, 588570069962,1045068291809,2678706653580] |