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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 138 |
| 3 | 412 |
| 4 | 1534 |
| 5 | 6220 |
| 6 | 21787 |
| 7 | 77434 |
| 8 | 287515 |
| 9 | 1062023 |
| 10 | 3895316 |
| 11 | 14409626 |
| 12 | 53456291 |
| 13 | 197797723 |
| 14 | 732348580 |
| 15 | 2715286164 |
| 16 | 10066456755 |
| 17 | 37323145513 |
| 18 | 138451984116 |
| 19 | 513710107898 |
| 20 | 1906237786210 |
| 21 | 7074744554297 |
| 22 | 26260602575051 |
[16,138,412,1534,6220,21787,77434,287515,1062023, 3895316,14409626,53456291,197797723,732348580, 2715286164,10066456755,37323145513,138451984116, 513710107898,1906237786210,7074744554297, 26260602575051] |