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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 1 |
| 6 | 37 |
| 7 | 5 |
| 8 | 111 |
| 9 | 21 |
| 10 | 345 |
| 11 | 84 |
| 12 | 1104 |
| 13 | 322 |
| 14 | 4 |
| 15 | 3611 |
| 16 | 1215 |
| 17 | 36 |
| 18 | 12016 |
| 19 | 4555 |
| 20 | 225 |
| 21 | 40548 |
| 22 | 17028 |
| 23 | 1210 |
| 24 | 138414 |
| 25 | 63636 |
| 26 | 5940 |
| 27 | 22 |
| 28 | 477076 |
| 29 | 238004 |
| 30 | 27534 |
| 31 | 286 |
| 32 | 1657956 |
| 33 | 891268 |
| 34 | 122850 |
| 35 | 2366 |
| 36 | 5802920 |
| 37 | 3342375 |
| 38 | 533625 |
| 39 | 15925 |
| 40 | 20436910 |
| 41 | 12552580 |
[1,1,2,5,13,1,37,5,111,21,345,84,1104,322,4,3611, 1215,36,12016,4555,225,40548,17028,1210,138414, 63636,5940,22,477076,238004,27534,286,1657956, 891268,122850,2366,5802920,3342375,533625,15925, 20436910,12552580] |