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| n | a(n) |
|---|---|
| 1 | 47 |
| 2 | 173 |
| 3 | 724 |
| 4 | 3160 |
| 5 | 13810 |
| 6 | 60368 |
| 7 | 263920 |
| 8 | 1153880 |
| 9 | 5044984 |
| 10 | 22057880 |
| 11 | 96442840 |
| 12 | 421674392 |
| 13 | 1843677400 |
| 14 | 8061072920 |
| 15 | 35245271896 |
| 16 | 154102230680 |
| 17 | 673778278360 |
| 18 | 2945948129048 |
| 19 | 12880513877080 |
| 20 | 56317230045080 |
| 21 | 246234772676824 |
[47,173,724,3160,13810,60368,263920,1153880, 5044984,22057880,96442840,421674392,1843677400, 8061072920,35245271896,154102230680,673778278360, 2945948129048,12880513877080,56317230045080, 246234772676824] |