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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 45 |
| 4 | 193 |
| 5 | 856 |
| 6 | 3887 |
| 7 | 17918 |
| 8 | 83588 |
| 9 | 393363 |
| 10 | 1864001 |
| 11 | 8881668 |
| 12 | 42512504 |
| 13 | 204252658 |
| 14 | 984469664 |
| 15 | 4757879335 |
| 16 | 23048473921 |
| 17 | 111881018651 |
| 18 | 544062911646 |
| 19 | 2649905710426 |
| 20 | 12924851464857 |
| 21 | 63120555634816 |
| 22 | 308611448436444 |
| 23 | 1510436638380017 |
| 24 | 7399491447414110 |
| 25 | 36280635687924703 |
| 26 | 178028980385601914 |
[1,3,11,45,193,856,3887,17918,83588,393363, 1864001,8881668,42512504,204252658,984469664, 4757879335,23048473921,111881018651,544062911646, 2649905710426,12924851464857,63120555634816, 308611448436444,1510436638380017,7399491447414110, 36280635687924703,178028980385601914] |