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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 101 |
| 3 | 465 |
| 4 | 1928 |
| 5 | 7812 |
| 6 | 31710 |
| 7 | 129402 |
| 8 | 529846 |
| 9 | 2172346 |
| 10 | 8908986 |
| 11 | 36534670 |
| 12 | 149811438 |
| 13 | 614276002 |
| 14 | 2518688490 |
| 15 | 10327233902 |
| 16 | 42344211246 |
| 17 | 173621959826 |
| 18 | 711894378346 |
| 19 | 2918949452350 |
| 20 | 11968441441998 |
| 21 | 49073678703842 |
[16,101,465,1928,7812,31710,129402,529846,2172346, 8908986,36534670,149811438,614276002,2518688490, 10327233902,42344211246,173621959826,711894378346, 2918949452350,11968441441998,49073678703842] |