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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 21 |
| 3 | 127 |
| 4 | 381 |
| 5 | 1911 |
| 6 | 5461 |
| 7 | 32767 |
| 8 | 98301 |
| 9 | 491511 |
| 10 | 1408981 |
| 11 | 8355711 |
| 12 | 25001341 |
| 13 | 125269879 |
| 14 | 357913941 |
| 15 | 2147483647 |
| 16 | 6442450941 |
| 17 | 32212254711 |
| 18 | 92341796821 |
| 19 | 547608330111 |
| 20 | 1638530022781 |
| 21 | 8209829984119 |
| 22 | 23456963876181 |
| 23 | 140735340838911 |
| 24 | 422201727483901 |
[1,7,21,127,381,1911,5461,32767,98301,491511, 1408981,8355711,25001341,125269879,357913941, 2147483647,6442450941,32212254711,92341796821, 547608330111,1638530022781,8209829984119, 23456963876181,140735340838911,422201727483901] |