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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 56 |
| 5 | 545 |
| 6 | 6696 |
| 7 | 100009 |
| 8 | 1756112 |
| 9 | 35480673 |
| 10 | 811332080 |
| 11 | 20696592521 |
| 12 | 583009540488 |
| 13 | 17972297981521 |
| 14 | 601961695890296 |
| 15 | 21765379980020265 |
| 16 | 844991974575946016 |
| 17 | 35056808550027808961 |
| 18 | 1547900555791042958688 |
| 19 | 72474037424646843142153 |
| 20 | 3586609339433026549298840 |
| 21 | 187062738581835989450074161 |
| 22 | 10255505482370456224398408872 |
| 23 | 589611389520200188085133153449 |
[1,2,9,56,545,6696,100009,1756112,35480673, 811332080,20696592521,583009540488,17972297981521, 601961695890296,21765379980020265, 844991974575946016,35056808550027808961, 1547900555791042958688,72474037424646843142153, 3586609339433026549298840, 187062738581835989450074161, 10255505482370456224398408872, 589611389520200188085133153449] |