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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 30 |
| 3 | 621 |
| 4 | 14196 |
| 5 | 351802 |
| 6 | 9179386 |
| 7 | 248533626 |
| 8 | 6917835992 |
| 9 | 196730606200 |
| 10 | 5691264122213 |
| 11 | 166961281712818 |
| 12 | 4955321842136163 |
| 13 | 148522859439511133 |
| 14 | 4489164688548477495 |
| 15 | 136677755757518772050 |
| 16 | 4187859771944659634378 |
| 17 | 129039023692329781903247 |
| 18 | 3995878021838502688832856 |
[1,2,30,621,14196,351802,9179386,248533626, 6917835992,196730606200,5691264122213, 166961281712818,4955321842136163, 148522859439511133,4489164688548477495, 136677755757518772050,4187859771944659634378, 129039023692329781903247, 3995878021838502688832856] |