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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 116 |
| 4 | 667 |
| 5 | 4529 |
| 6 | 26558 |
| 7 | 170468 |
| 8 | 1067723 |
| 9 | 6694705 |
| 10 | 41981191 |
| 11 | 263257030 |
| 12 | 1651418740 |
| 13 | 10357579301 |
| 14 | 64961533372 |
| 15 | 407436733800 |
| 16 | 2555438539179 |
| 17 | 16027677245855 |
| 18 | 100525225308587 |
| 19 | 630492043325935 |
| 20 | 3954433363194971 |
[1,17,116,667,4529,26558,170468,1067723,6694705, 41981191,263257030,1651418740,10357579301, 64961533372,407436733800,2555438539179, 16027677245855,100525225308587,630492043325935, 3954433363194971] |