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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 65 |
| 6 | 205 |
| 7 | 713 |
| 8 | 2399 |
| 9 | 8807 |
| 10 | 31423 |
| 11 | 118403 |
| 12 | 442903 |
| 13 | 1696475 |
| 14 | 6569623 |
| 15 | 25553523 |
| 16 | 101307245 |
| 17 | 400537565 |
| 18 | 1612283869 |
| 19 | 6479393097 |
| 20 | 26354237909 |
| 21 | 107481783441 |
| 22 | 440881860189 |
| 23 | 1819850183485 |
| 24 | 7525644193561 |
| 25 | 31351482619465 |
| 26 | 130708930200313 |
| 27 | 548353337148221 |
| 28 | 2304188571803413 |
[1,1,3,7,21,65,205,713,2399,8807,31423,118403, 442903,1696475,6569623,25553523,101307245, 400537565,1612283869,6479393097,26354237909, 107481783441,440881860189,1819850183485, 7525644193561,31351482619465,130708930200313, 548353337148221,2304188571803413] |