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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 16 |
| 4 | 119 |
| 5 | 934 |
| 6 | 7463 |
| 7 | 60145 |
| 8 | 486605 |
| 9 | 3943960 |
| 10 | 31992446 |
| 11 | 259613953 |
| 12 | 2107099586 |
| 13 | 17103200263 |
| 14 | 138830852135 |
| 15 | 1126943433241 |
| 16 | 9147906485462 |
| 17 | 74257943539984 |
| 18 | 602788362550355 |
| 19 | 4893134369283898 |
| 20 | 39720031331092499 |
| 21 | 322427514601782961 |
| 22 | 2617306853237874173 |
[1,2,16,119,934,7463,60145,486605,3943960, 31992446,259613953,2107099586,17103200263, 138830852135,1126943433241,9147906485462, 74257943539984,602788362550355,4893134369283898, 39720031331092499,322427514601782961, 2617306853237874173] |