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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 14 |
| 2 | 140 |
| 3 | 1190 |
| 4 | 9170 |
| 5 | 66122 |
| 6 | 454328 |
| 7 | 3009050 |
| 8 | 19359620 |
| 9 | 121664410 |
| 10 | 749879508 |
| 11 | 4546925922 |
| 12 | 27188341530 |
| 13 | 160624341990 |
| 14 | 939009926520 |
| 15 | 5438826037974 |
| 16 | 31244200818306 |
| 17 | 178173537480330 |
| 18 | 1009366349014100 |
| 19 | 5684102310204850 |
| 20 | 31836106214747590 |
| 21 | 177430881586034110 |
[1,14,140,1190,9170,66122,454328,3009050,19359620, 121664410,749879508,4546925922,27188341530, 160624341990,939009926520,5438826037974, 31244200818306,178173537480330,1009366349014100, 5684102310204850,31836106214747590, 177430881586034110] |