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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 61 |
| 3 | 385 |
| 4 | 572 |
| 5 | 3851 |
| 6 | 44623 |
| 7 | 347576 |
| 8 | 1650710 |
| 9 | 12360130 |
| 10 | 106235031 |
| 11 | 807578953 |
| 12 | 5406175833 |
| 13 | 41246496374 |
| 14 | 328408364493 |
| 15 | 2509089355110 |
| 16 | 18435763834038 |
| 17 | 141054581587168 |
| 18 | 1100340622468942 |
| 19 | 8442342552511565 |
| 20 | 63751061176641632 |
[1,61,385,572,3851,44623,347576,1650710,12360130, 106235031,807578953,5406175833,41246496374, 328408364493,2509089355110,18435763834038, 141054581587168,1100340622468942,8442342552511565, 63751061176641632] |