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| n | a(n) |
|---|---|
| 1 | 307 |
| 2 | 1326 |
| 3 | 3147 |
| 4 | 2745 |
| 5 | 8114 |
| 6 | 29959 |
| 7 | 111707 |
| 8 | 425010 |
| 9 | 1602835 |
| 10 | 6076455 |
| 11 | 23038228 |
| 12 | 87322215 |
| 13 | 331059861 |
| 14 | 1255146516 |
| 15 | 4758551951 |
| 16 | 18041027869 |
| 17 | 68398734846 |
| 18 | 259319077335 |
| 19 | 983153218535 |
| 20 | 3727416848414 |
| 21 | 14131709526987 |
| 22 | 53577378404731 |
[307,1326,3147,2745,8114,29959,111707,425010, 1602835,6076455,23038228,87322215,331059861, 1255146516,4758551951,18041027869,68398734846, 259319077335,983153218535,3727416848414, 14131709526987,53577378404731] |