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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 71 |
| 4 | 1261 |
| 5 | 29906 |
| 6 | 887751 |
| 7 | 31657851 |
| 8 | 1318279586 |
| 9 | 62783681421 |
| 10 | 3365947782611 |
| 11 | 200610405843926 |
| 12 | 13157941480889921 |
| 13 | 941848076798467801 |
| 14 | 73060842413607398806 |
| 15 | 6105266987293752470991 |
| 16 | 546770299628690541571901 |
| 17 | 52244284936267317229542466 |
| 18 | 5305131708827069245129523591 |
[1,6,71,1261,29906,887751,31657851,1318279586, 62783681421,3365947782611,200610405843926, 13157941480889921,941848076798467801, 73060842413607398806,6105266987293752470991, 546770299628690541571901, 52244284936267317229542466, 5305131708827069245129523591] |