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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 105 |
| 3 | 385 |
| 4 | 1365 |
| 5 | 1785 |
| 6 | 2805 |
| 7 | 3135 |
| 8 | 6545 |
| 9 | 10465 |
| 10 | 11305 |
| 11 | 17255 |
| 12 | 20615 |
| 13 | 26565 |
| 14 | 40755 |
| 15 | 106743 |
| 16 | 171717 |
| 17 | 255255 |
| 18 | 279565 |
| 19 | 327845 |
| 20 | 707455 |
| 21 | 886445 |
| 22 | 983535 |
| 23 | 1181895 |
| 24 | 1752465 |
| 25 | 3949491 |
| 26 | 8070699 |
| 27 | 10163195 |
| 28 | 13441645 |
| 29 | 15069565 |
| 30 | 30489585 |
| 31 | 37495115 |
| 32 | 40324935 |
[1,105,385,1365,1785,2805,3135,6545,10465,11305, 17255,20615,26565,40755,106743,171717,255255, 279565,327845,707455,886445,983535,1181895, 1752465,3949491,8070699,10163195,13441645, 15069565,30489585,37495115,40324935] |