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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 41 |
| 5 | 165 |
| 6 | 693 |
| 7 | 2975 |
| 8 | 13102 |
| 9 | 58543 |
| 10 | 265533 |
| 11 | 1216437 |
| 12 | 5625630 |
| 13 | 26208715 |
| 14 | 122883878 |
| 15 | 579308565 |
| 16 | 2743787003 |
| 17 | 13048731447 |
| 18 | 62277382336 |
| 19 | 298169598323 |
| 20 | 1431550417591 |
| 21 | 6890222494696 |
| 22 | 33237555228170 |
| 23 | 160656725334807 |
| 24 | 777962747662943 |
| 25 | 3773430268357265 |
| 26 | 18330224672912397 |
| 27 | 89165583321567972 |
[1,1,3,11,41,165,693,2975,13102,58543,265533, 1216437,5625630,26208715,122883878,579308565, 2743787003,13048731447,62277382336,298169598323, 1431550417591,6890222494696,33237555228170, 160656725334807,777962747662943,3773430268357265, 18330224672912397,89165583321567972] |