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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 62 |
| 6 | 201 |
| 7 | 605 |
| 8 | 2011 |
| 9 | 6502 |
| 10 | 22101 |
| 11 | 73668 |
| 12 | 254610 |
| 13 | 855688 |
| 14 | 2992543 |
| 15 | 10303873 |
| 16 | 36346419 |
| 17 | 126557708 |
| 18 | 449930313 |
| 19 | 1574917880 |
| 20 | 5634214960 |
| 21 | 19949390598 |
| 22 | 71696662513 |
| 23 | 255420242076 |
| 24 | 922281690320 |
| 25 | 3296806030186 |
| 26 | 11949223489294 |
| 27 | 42998187306604 |
| 28 | 156311046178142 |
| 29 | 564673749263750 |
| 30 | 2059135123715593 |
[1,1,3,7,21,62,201,605,2011,6502,22101,73668, 254610,855688,2992543,10303873,36346419,126557708, 449930313,1574917880,5634214960,19949390598, 71696662513,255420242076,922281690320, 3296806030186,11949223489294,42998187306604, 156311046178142,564673749263750,2059135123715593] |