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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 15 |
| 4 | 64 |
| 5 | 210 |
| 6 | 630 |
| 7 | 1288 |
| 8 | 736 |
| 9 | 4959 |
| 10 | 9850 |
| 11 | 14421 |
| 12 | 6336 |
| 13 | 34840 |
| 14 | 57134 |
| 15 | 20805 |
| 16 | 28288 |
| 17 | 141933 |
| 18 | 208818 |
| 19 | 253099 |
| 20 | 89200 |
| 21 | 107856 |
| 22 | 583462 |
| 23 | 680340 |
| 24 | 56304 |
| 25 | 1045675 |
| 26 | 1367210 |
| 27 | 1553553 |
| 28 | 497056 |
| 29 | 2242164 |
| 30 | 687090 |
| 31 | 3155986 |
| 32 | 979456 |
| 33 | 1092861 |
| 34 | 5336674 |
| 35 | 1580845 |
| 36 | 1779408 |
| 37 | 7797898 |
| 38 | 9370838 |
| 39 | 2622789 |
| 40 | 756400 |
[1,4,15,64,210,630,1288,736,4959,9850,14421,6336, 34840,57134,20805,28288,141933,208818,253099, 89200,107856,583462,680340,56304,1045675,1367210, 1553553,497056,2242164,687090,3155986,979456, 1092861,5336674,1580845,1779408,7797898,9370838, 2622789,756400] |