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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 33 |
| 4 | 139 |
| 5 | 565 |
| 6 | 2271 |
| 7 | 9097 |
| 8 | 36403 |
| 9 | 145629 |
| 10 | 582535 |
| 11 | 2330161 |
| 12 | 9320667 |
| 13 | 37282693 |
| 14 | 149130799 |
| 15 | 596523225 |
| 16 | 2386092931 |
| 17 | 9544371757 |
| 18 | 38177487063 |
| 19 | 152709948289 |
| 20 | 610839793195 |
| 21 | 2443359172821 |
| 22 | 9773436691327 |
| 23 | 39093746765353 |
| 24 | 156374987061459 |
| 25 | 625499948245885 |
| 26 | 2501999792983591 |
[0,1,7,33,139,565,2271,9097,36403,145629,582535, 2330161,9320667,37282693,149130799,596523225, 2386092931,9544371757,38177487063,152709948289, 610839793195,2443359172821,9773436691327, 39093746765353,156374987061459,625499948245885, 2501999792983591] |