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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 12 |
| 3 | 12 |
| 4 | 207 |
| 5 | 470 |
| 6 | 4073 |
| 7 | 13314 |
| 8 | 85974 |
| 9 | 338148 |
| 10 | 1892213 |
| 11 | 8198076 |
| 12 | 42661873 |
| 13 | 194441436 |
| 14 | 974764224 |
| 15 | 4561903748 |
| 16 | 22432271947 |
| 17 | 106441266034 |
| 18 | 518196714761 |
| 19 | 2476544809950 |
| 20 | 11994439907546 |
| 21 | 57537238641980 |
| 22 | 277917546512145 |
[0,12,12,207,470,4073,13314,85974,338148,1892213, 8198076,42661873,194441436,974764224,4561903748, 22432271947,106441266034,518196714761, 2476544809950,11994439907546,57537238641980, 277917546512145] |