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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 46 |
| 4 | 669 |
| 5 | 11096 |
| 6 | 196888 |
| 7 | 3596104 |
| 8 | 66867564 |
| 9 | 1258801076 |
| 10 | 23925376862 |
| 11 | 458284630844 |
| 12 | 8835496339452 |
| 13 | 171286387714900 |
| 14 | 3336406717216564 |
| 15 | 65257828878990784 |
| 16 | 1281049596756607960 |
| 17 | 25228921286295314736 |
| 18 | 498287389997552607290 |
| 19 | 9866927329534881618772 |
| 20 | 195837489338961245840240 |
[1,5,46,669,11096,196888,3596104,66867564, 1258801076,23925376862,458284630844,8835496339452, 171286387714900,3336406717216564, 65257828878990784,1281049596756607960, 25228921286295314736,498287389997552607290, 9866927329534881618772,195837489338961245840240] |