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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 45 |
| 3 | 164 |
| 4 | 934 |
| 5 | 4267 |
| 6 | 21949 |
| 7 | 106793 |
| 8 | 529984 |
| 9 | 2617548 |
| 10 | 12938179 |
| 11 | 63986777 |
| 12 | 316244862 |
| 13 | 1563877465 |
| 14 | 7731246308 |
| 15 | 38227036552 |
| 16 | 188999363652 |
| 17 | 934471931880 |
| 18 | 4620268994057 |
| 19 | 22843909984025 |
| 20 | 112946725741085 |
| 21 | 558440468796391 |
[2,45,164,934,4267,21949,106793,529984,2617548, 12938179,63986777,316244862,1563877465,7731246308, 38227036552,188999363652,934471931880, 4620268994057,22843909984025,112946725741085, 558440468796391] |