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| n | a(n) |
|---|---|
| 1 | 220 |
| 2 | 546 |
| 3 | 1240 |
| 4 | 3384 |
| 5 | 8416 |
| 6 | 24420 |
| 7 | 64240 |
| 8 | 194124 |
| 9 | 527920 |
| 10 | 1640076 |
| 11 | 4548400 |
| 12 | 14411004 |
| 13 | 40441936 |
| 14 | 130023180 |
| 15 | 367611280 |
| 16 | 1195404444 |
| 17 | 3396165040 |
| 18 | 11145399276 |
| 19 | 31767426160 |
| 20 | 105049443324 |
| 21 | 300084387856 |
| 22 | 998758590540 |
| 23 | 2857390403920 |
[220,546,1240,3384,8416,24420,64240,194124,527920, 1640076,4548400,14411004,40441936,130023180, 367611280,1195404444,3396165040,11145399276, 31767426160,105049443324,300084387856, 998758590540,2857390403920] |