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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 50 |
| 5 | 70 |
| 6 | 201 |
| 7 | 210 |
| 8 | 540 |
| 9 | 615 |
| 10 | 1065 |
| 11 | 1001 |
| 12 | 2745 |
| 13 | 1820 |
| 14 | 3430 |
| 15 | 4110 |
| 16 | 6751 |
| 17 | 4845 |
| 18 | 10950 |
| 19 | 7315 |
| 20 | 15930 |
| 21 | 13776 |
| 22 | 17655 |
| 23 | 14950 |
| 24 | 38775 |
| 25 | 22960 |
| 26 | 32851 |
| 27 | 35510 |
| 28 | 53865 |
| 29 | 35960 |
| 30 | 81015 |
| 31 | 46376 |
| 32 | 92741 |
| 33 | 73920 |
| 34 | 90270 |
| 35 | 88515 |
| 36 | 180852 |
| 37 | 91390 |
| 38 | 137845 |
| 39 | 139230 |
| 40 | 241235 |
| 41 | 135751 |
[1,5,15,50,70,201,210,540,615,1065,1001,2745,1820, 3430,4110,6751,4845,10950,7315,15930,13776,17655, 14950,38775,22960,32851,35510,53865,35960,81015, 46376,92741,73920,90270,88515,180852,91390,137845, 139230,241235,135751] |