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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 32 |
| 3 | 336 |
| 4 | 3610 |
| 5 | 26996 |
| 6 | 229348 |
| 7 | 1620034 |
| 8 | 12071462 |
| 9 | 82550864 |
| 10 | 572479244 |
| 11 | 3808019582 |
| 12 | 25304433030 |
| 13 | 164452629818 |
| 14 | 1062773834046 |
| 15 | 6777328517896 |
| 16 | 42944798886570 |
| 17 | 269706791277978 |
| 18 | 1683956271732804 |
| 19 | 10445800698724066 |
| 20 | 64470330298173718 |
| 21 | 395897522698282286 |
[1,32,336,3610,26996,229348,1620034,12071462, 82550864,572479244,3808019582,25304433030, 164452629818,1062773834046,6777328517896, 42944798886570,269706791277978,1683956271732804, 10445800698724066,64470330298173718, 395897522698282286] |