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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 48 |
| 5 | 166 |
| 6 | 622 |
| 7 | 2326 |
| 8 | 9309 |
| 9 | 36739 |
| 10 | 151832 |
| 11 | 620493 |
| 12 | 2633507 |
| 13 | 11037726 |
| 14 | 47677709 |
| 15 | 203638448 |
| 16 | 892014016 |
| 17 | 3865883495 |
| 18 | 17116446248 |
| 19 | 75049236217 |
| 20 | 335181357964 |
| 21 | 1483617411572 |
| 22 | 6673221538285 |
| 23 | 29770554253264 |
| 24 | 134701250227594 |
| 25 | 604910695461140 |
| 26 | 2750750692731513 |
| 27 | 12422712428685783 |
[1,2,5,14,48,166,622,2326,9309,36739,151832, 620493,2633507,11037726,47677709,203638448, 892014016,3865883495,17116446248,75049236217, 335181357964,1483617411572,6673221538285, 29770554253264,134701250227594,604910695461140, 2750750692731513,12422712428685783] |