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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 46 |
| 5 | 156 |
| 6 | 561 |
| 7 | 2037 |
| 8 | 7525 |
| 9 | 27874 |
| 10 | 103741 |
| 11 | 386386 |
| 12 | 1440946 |
| 13 | 5374772 |
| 14 | 20054945 |
| 15 | 74835209 |
| 16 | 279273961 |
| 17 | 1042224066 |
| 18 | 3889577781 |
| 19 | 14515950582 |
| 20 | 54174058390 |
| 21 | 202179773644 |
| 22 | 754544416081 |
| 23 | 2815995989821 |
| 24 | 10509437228941 |
| 25 | 39221745831842 |
| 26 | 146377537461485 |
[1,2,5,14,46,156,561,2037,7525,27874,103741, 386386,1440946,5374772,20054945,74835209, 279273961,1042224066,3889577781,14515950582, 54174058390,202179773644,754544416081, 2815995989821,10509437228941,39221745831842, 146377537461485] |