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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 32 |
| 4 | 112 |
| 5 | 416 |
| 6 | 1512 |
| 7 | 5472 |
| 8 | 19904 |
| 9 | 72396 |
| 10 | 263136 |
| 11 | 956480 |
| 12 | 3477232 |
| 13 | 12641136 |
| 14 | 45954928 |
| 15 | 167063792 |
| 16 | 607344064 |
| 17 | 2207938656 |
| 18 | 8026742304 |
| 19 | 29180448720 |
| 20 | 106082737616 |
| 21 | 385653691936 |
| 22 | 1402007389776 |
| 23 | 5096865080336 |
| 24 | 18529170684512 |
[1,12,32,112,416,1512,5472,19904,72396,263136, 956480,3477232,12641136,45954928,167063792, 607344064,2207938656,8026742304,29180448720, 106082737616,385653691936,1402007389776, 5096865080336,18529170684512] |