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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 23 |
| 4 | 165 |
| 5 | 1328 |
| 6 | 13193 |
| 7 | 145076 |
| 8 | 1774515 |
| 9 | 23600723 |
| 10 | 338704176 |
| 11 | 5202002092 |
| 12 | 85007211518 |
| 13 | 1470699469052 |
| 14 | 26828468813710 |
| 15 | 514213843983674 |
| 16 | 10323889080831256 |
| 17 | 216536421271101354 |
| 18 | 4733415248988274281 |
| 19 | 107609706100197846274 |
| 20 | 2539397701858619916499 |
[1,5,23,165,1328,13193,145076,1774515,23600723, 338704176,5202002092,85007211518,1470699469052, 26828468813710,514213843983674,10323889080831256, 216536421271101354,4733415248988274281, 107609706100197846274,2539397701858619916499] |