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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 1 |
| 5 | 5 |
| 6 | 15 |
| 7 | 35 |
| 8 | 1 |
| 9 | 9 |
| 10 | 45 |
| 11 | 165 |
| 12 | 495 |
| 13 | 1287 |
| 14 | 3003 |
| 15 | 6435 |
| 16 | 1 |
| 17 | 17 |
| 18 | 153 |
| 19 | 969 |
| 20 | 4845 |
| 21 | 20349 |
| 22 | 74613 |
| 23 | 245157 |
| 24 | 735471 |
| 25 | 2042975 |
| 26 | 5311735 |
| 27 | 13037895 |
| 28 | 30421755 |
| 29 | 67863915 |
| 30 | 145422675 |
| 31 | 300540195 |
| 32 | 1 |
| 33 | 33 |
| 34 | 561 |
| 35 | 6545 |
| 36 | 58905 |
| 37 | 435897 |
| 38 | 2760681 |
| 39 | 15380937 |
| 40 | 76904685 |
| 41 | 350343565 |
[1,1,3,1,5,15,35,1,9,45,165,495,1287,3003,6435,1, 17,153,969,4845,20349,74613,245157,735471,2042975, 5311735,13037895,30421755,67863915,145422675, 300540195,1,33,561,6545,58905,435897,2760681, 15380937,76904685,350343565] |